The green dilemma: Reflections of a Generation Y consumer cohort on green purchase behaviour

Green consumerism has garnered much scholarly interest in recent years. However, research on the influence of the Social Dilemma Theory (SDT) on green purchase behaviour has been scarce. Using data generated from sixteen in-depth-interviews, the present study identified perceived efficacy, perceived cost, in-group and self-identity, trust and peer influence as the main antecedents of SDT that influence green purchase behaviour. The findings of the study imply that to promote and institutionalise green purchase behaviour, marketers need to enhance perceived efficacy, trust in green products, reduce perceived cost, align green products with the consumers’ sought image and utilise peer networks when structuring green marketing messages.


Introduction
The production and marketing of green products has proliferated with consumers reporting significant levels of environmental concern (Gleim, Smith, Andrews & Cronin, 2013:44). At the epicentre of the trend towards sustainable consumption are Generation Y consumers (Atkinson & Rosenthal, 2014:42;Smith & Brower, 2012:357). Generation Y represents a cohort of individuals who were born during an era of environmental consciousness and this group is more apt to adopt pro-environmental behaviours than other cohorts (Awad, 2011:60;Lee, 2008:573). While there is no consensus on specific cut-off dates, the general understanding is that Generation Y consumers were born between 1978 and 2000 (Kotler & Armstrong, 2010:98). In 2014, Generation Y consumers in South Africa were aged between 14 and 36 years, constituting approximately 37 percent of the total population (Statistics South Africa, 2011:28). According to Lee (2009:8), the Generation Y cohort represents a significant citizenry that has the potential to drive green consumerism.
However, in spite of the potential of the Generation Y cohort to spearhead green consumerism, empirical evidence suggests that the demand of green products remains low in major markets (Carrington, Neville & Whitwell, 2010:140). It is estimated that green products account for a paltry market share of less than 4 percent globally (Ritter, Borchardt, Vaccaro, Giancarlo, Pereira & Almeida, 2014:1). As green products continue to struggle to gain market appeal, marketers noted the existence of the 'green paradox' (Longoni, Gollwitzer & Oettingen, 2014:158), also known as the 'sustainability dilemma' (Jayanti & Gowda, 2014:130). The green paradox or sustainability dilemma emanates from the mismatch between the purchase of green products and the reported increase in environmental concern among consumers (Tseng & Hung, 2013:181). This dilemma is recognised as the foremost impediment of green purchase behaviour (Gupta & Ogden, 2009:386).
As the gap between environmental concern and consumption of green products continues to widen, numerous studies have characterised the purchase of green products as a social dilemma (Gupta & Ogden, 2009:386;Jayanti & Gowda, 2014:130;Irwin, Edwards & Tamburello, 2014:2). The decision to purchase green products amounts to a social dilemma in that most consumers are trapped in the conundrum of balancing individual and collective societal needs in consumption settings (Gupta & Ogden, 2009:386). Specifically, the social dilemma is perceived when individuals who are intrinsically driven to satisfy individual needs attempt to reconcile societal needs and maximise self-interest when making purchase decisions (Davari & Strutton, 2014:1). Thus, Gupta and Ogden (2009:386) contend that the Social Dilemma Theory (SDT) potentially explain the attitude-behaviour gap that characterises green purchase behaviour.

Research objective
Given the background of the persistent existence of the environmental concern-purchase behaviour gap, conflict between self-identity and societal interests, the objective of the present study was to provide insights on the influence of the SDT on green purchase behaviour of Generation Y consumers. The dearth of research in this area in the context of an emerging market such as South Africa necessitated the need for such a study.

Social dilemma theory and green purchase behaviour
The phrase 'social dilemma' was popularised by Dawes (1980:173) to refer to situations whereby the pursuit and maximisation of immediate individual needs often translates into long-term societal deprivation. The social dilemma manifests itself when there is a conflict between short-term individual needs and long-term altruistic needs (Van Lange, Joireman, Parks & Van Dijk, 2013:125). Conceptually, social dilemmas are characterised by a noncooperative choice behaviour that is principally motivated by the desire for personal gratification with the inherent danger of causing long-term societal harm (Dawes, 1980:173). From an individual perspective, it is considered irrational to engage in the protection of a public good such as the natural environment as everyone benefits regardless of the level of participation (Molenmaker, De Kwaadsteniet & Van Dijk, 2014:175). Conversely, if everyone attempts to maximise self-interest, the benefits are forfeited by all (Kollock, 1998:183).
Environmental protection is classified as a public good due to its non-rivalness and nonexcludability (Hardin, 1982:17). A resource qualifies as non-rival if everyone can benefit from it and non-excludable if one's benefit from it does not preclude others from doing so (Irwin et al., 2014:4). In a typical case of the 'tragedy of commons' (Hardin, 1968(Hardin, :1245, the benefits of a clean environment are enjoyed by all regardless of the degree of cooperation (Irwin et al., 2014:4).Within the natural environment domain, social dilemmas include decisions on environmental protection including the purchase of green products (Van Lange et al., 2013:125). The social dilemma emanates from the fact that green purchase behaviour is considered an altruistic, highly costly act that benefits the society including non-participants (Griskevicius, Tybur & Van den Bergh, 2010:392). For instance, individual consumers sacrifice to buy premium priced green products yet everyone benefits from a sustained natural environment including non-green product buyers (Gleim et al., 2013:44). Hence, the decision whether to buy (societal benefit) or not to buy (individual benefit) a green product is framed as a social dilemma (Gupta & Ogden, 2009:377).
The antecedents of SDT that influence green purchase behaviour include social value orientation, self-efficacy, peer influence, the degree of cooperation of others and the cost of cooperation (Gupta & Ogden, 2009:377;Van Lange et al., 2013:125).

Social value orientation
The purchase of environmentally friendly products is regarded as a socially acceptable gesture with a high social value attachment (Webb, Mohr & Harris, 2008:93). Van Lange, Liebrand, Messick and Wilke (1992:17) define social value orientation as "...preferences for particular distribution of outcomes to oneself and others." Social value oriented individuals are altruistic in nature and display a higher propensity to pursue collective goals as opposed to personal ones (Lee, Kim, Kim & Choi, 2014:2100. Social value is presumed to be more influential in shaping purchase intentions within a collectivist cultural setting where consumers are more expected to comply with social norms than in individualist cultures (Oliver & Lee, 2010:98). Social value orientation encompasses behavioural actions that enhance in-group and self-identity (Van Lange et al., 1992:17).

In-group social identity
Past studies revealed that promoting in-group identity enhances cooperative behaviour in resource preservation dilemmas (Gupta & Ogden, 2009:388;Kerr, 1989:287). This is so because in-group identity entails the quest for identification with a significant social group and compels an individual to comply with the expectations of peers through the purchase of specific products or services (Bearden, Netemeyer & Teel, 1989:473). In particular, social identification plays a key role in buying behaviour as it enhances approval from an esteemed reference group (Bartels & Reinders, 2010:350). The Generation Y consumers consider an environmentally sensitive group as a socially appealing and inspiring segment of the population with which they would like to be associated (Smith & Brower, 2012:357). The strong power of in-group identity suggests a possible group effect in environmental behaviour, a trend more noticeable among young consumers (Lee, 2009:92).
Social value is particularly important to Generation Y consumers as they are characterised by the desire for peer acceptance, conformity and affiliation (Williams & Page, 2011:44). In an endeavour to connect with peers, Oliver and Lee (2010:99) note that Generation Y consumers perceive purchase decisions as a creation of social identities. However, there is an inherent conflict within the Generation Y cohort to balance in-group identity and selfinterest (Hume, 2010:392). Moreover, the effect of social value on consumer buyer behaviour tends to vary within the cultural domains of collectivism and individualism (Cheah & Phau, 2011:453).

Self-interest
The overriding concern in social dilemmas is the conflict between self-interest and collective benefits (Lee et al., 2014(Lee et al., :2097. Apart from being regarded as an altruistic act, the consumption of green products is also associated with the quest for status (Griskevicius et al., 2010:394). For instance, Schultz and Zelezny (1999:255) noted the prevalence of egoistic environmental attitudes that have the potential of stimulating or inhibiting proenvironmental behaviour performance. In addition, De Young (2000:515) suggests that some individuals find environmental behaviour "as worth engaging in because of the personal, internal contentment that participating in such behaviours provides." Accordingly, Sexton and Sexton (2012:6) opine that green consumption has a 'green-signalling' effect as it portrays an individual's pro-social behaviour as demonstrated by the willingness to incur costs associated with the purchase of green products such as a high price.
Given the status enhancing benefits of engaging in pro-environmental behaviour, consumers are more likely to engage in competitive altruism in the presence of peers whilst at the same time seen as caring for the well-being of the environment (Nunes, Dreze & Han, 2011:199). As green products are more expensive than conventional ones, status seeking consumers are more likely to buy green products to signal their ability to incur costs on behalf of others and the environment (Griskevicius et al., 2010:393). As a status driven cohort, Generation Y consumers however, perceive high social risk if product purchase decisions fail to meet the expectations of peers (Batra & Kazmi, 2008:127). Apart from social value orientation, the consumption of green products is also influenced by the cost of cooperation (Gupta & Ogden, 2009:387).

Cost of cooperation
The performance of green purchase behaviour is associated with costs such as high prices, extensive information search, unavailability of green products, risk perception and poor quality (Lea & Worsley, 2005:860;Radman, 2005:269). Within the context of green products, Elliott (2013:299) conceptualises price under the auspices of the willingness of consumers to pay the premium price associated with green products. For instance, Shafie and Rennie (2012:365) observed that the premium price of green products remains as one of the major deterrents of green product consumption.
Moreover, the perception of risk is heightened by a scarcity of effective standards to monitor the production of green products (Radman, 2005:271). Specifically, the perception of risk is compounded by the scepticism associated with the credibility of eco-labels and green product advertisements (Padel & Foster, 2005:620). Thus, risk adverse consumers would rather remain loyal to known conventional products than experiment with relatively unknown green products (Smith & Paladino, 2010:97). In social dilemma situations, the decision to engage in cooperative behaviour also depends on the perception of self-efficacy (Van Lange et al., 1992:18).

Self-efficacy
Perceived self-efficacy is defined as 'beliefs in one's capabilities to organise and execute the courses of action required to produce given levels of attainments' (Bandura, 1998:624). As an individual centric concept, self-efficacy largely depends on one's willingness to engage in certain behaviours, core competencies and value systems (Carrington et al., 2010:146).
Based on the Self-Efficacy Theory (Bandura, 1977:193), consumers are likely to engage in pro-environmental behaviour if they believe that they have the capacity to reduce the negative effects of climate change. Similarly, the Theory of Planned Behaviour (Ajzen, 1991:183) employs the perceived behaviour control construct to refer to an individual's perception of the easiness and effectiveness of performing the behaviour of interest. Perceived behavioural control also refers to an individual's perceptions of the ability to perform a given behaviour (Paco & Raposo, 2009:431). Thus, the concept of self-efficacy is based on the premise that consumers' attitudes and responses to environmental appeals are a function of the belief that their efforts can positively address environmental problems (Awad, 2011:61).

Research approach and sample
A qualitative research approach in the form of semi-structured in-depth interviews was adopted to understand the influence of SDT on green purchase behaviour of Generation Y consumers. This approach was preferred over a quantitative one as it allowed the "phenomenon of interest to unfold naturally" (Patton, 2001:39). The sample was drawn from two Higher Education Institutions (HEIs), namely a private college and public university of technology. Using this sample, data were collected from a purposively selected Generation Y student sample comprising sixteen participants (n=16). The student population was selected because young students are regarded as future consumers, with the ability to influence longterm consumption patterns (Atkinson & Rosenthal, 2014:42). Of the sixteen participants, nine (56%) were female and seven (44%) were male. Participants ranged in age from 20 to 35 years, with a mean age of 25 years.

Instrument and procedures
An interview guide was designed after a comprehensive literature review. It was pre-tested with three participants to assess the suitability of questions, sequence of questions and the duration of the interview (Surujlal, 2011:121). Following the pre-test, it was refined with minor adjustments. The interview guide comprised questions on: motivation to buy or not to buy green products, experience of consumers with green products, sources of green product information, basis for green purchase behaviour and the possibility to continue to engage in green purchase behaviour. In line with the concept of informed consent, an invitation letter was sent to all participants prior to interviews. The letter briefly explained the purpose of the interview and the interview procedures. The ethical clearance to conduct the study was obtained from the participating two HEIs.
The interviews were conducted at two campuses over a period of 30 days between May and July 2014. The interview commenced with a general broad question to put the interviewees at ease. The interviews were recorded on audiotape and notes were taken simultaneously by the interviewer to supplement the taped discussions. The tape recorder was positioned close enough between the researcher and each participant to record the conversation. As suggested by Holloway and Wheeler (2002:237), key points were noted discreetly to avoid distracting the participants and the flow of the interview. Where necessary, probes were used to clarify certain issues.
The audio tapes and interview notes were labelled properly for each interview with dates and pseudonym names including the date of the interview and the gender of the participants. All the interviews were conducted by the researchers and were between 60-90 minutes duration. The interviews were conducted in line with ethical considerations such as respect, honesty, confidentiality and anonymity (Surujlal, 2011:122).The concept of technical saturation was used to determine the sample size. Technical saturation refers to the point at which recurrence of previously generated data occurs (Guest, Bunce & Johnson, 2006:60). Technical saturation was deemed to be reached by the sixteenth interview as no new information emerged from subsequent interviews.

Data analysis
Following the verbatim transcription of the interviews, the researcher and two professors analysed all the transcripts from in-depth interviews by employing the six-stage process recommended by Braun and Clarke (2006:6). Data analysis commenced by reading through the transcribed notes and listening to the interview recorded tapes to become familiar with the data. This was further done in order to capture all the key aspects raised in the interview and ascertain the depth and credibility of data (Braun & Clarke, 2006:86). After sifting through the data, the second stage took the inductive form of open coding. Open coding refers to the process of clustering interview transcripts that appeared to pertain to similar ideas into categories and sub-categories (Glesne, 2011:187;Lawrence & Tar, 2013:32).
The creation of themes and sub-themes followed the open coding stage. According to Leininger (1985:60), theme creation involves "bringing together components or fragments of ideas or experiences, which often are meaningless when viewed alone." Thematic analysis was undertaken to create themes from the interview transcripts. Thematic analysis is defined as a meticulous process of identifying, analysing and reporting themes that emerge from a qualitative study (Braun & Clarke, 2006:79). Thematic analysis was utilised because it is regarded by Braun and Clarke (2006:78) as "a foundational method for qualitative analysis." The major advantage of thematic analysis is that, it allows the researcher to comprehensively scrutinise interviews transcripts and glean for all possible themes (Glesne, 2011:187).
The fourth stage involved theme refinement (Braun & Clarke, 2006:91). Also known as axial coding (Lawrence & Tar, 2013:32), theme refinement involves a detailed analysis of themes and sub-themes in order to search for possible relationships amongst them (Chen, Chang & Wu, 2012:374). Theme refinement followed a two-step process. Firstly, the themes and subthemes were reviewed to verify whether the identified themes were supported by interview transcripts. Secondly, the themes were re-analysed to check for the relationships between themes and sub-themes (Braun & Clarke, 2006:91). In instances where the themes and subthemes were related, they were further collapsed to form one dominant theme (Chen et al., 2012:374).
The fifth stage involved mapping the themes that emanated from the analysis. The mapping process took the form of naming and defining precisely the themes that emerged in the analysis of the data. The aim of this step was to identify the essence of each theme and to determine the aspects of the data captured by each theme (Braun & Clarke, 2006:92). The data were analysed using an iterative and recursive process to ensure that all information relating to the study was aptly captured (Creswell, 2009:189). In the final stage, the identified themes were related back to the research question and conclusions were inferred based on the generated themes.

Credibility and trustworthiness of the study
The reliability and validity of the present study was enhanced through methodological coherence, interview guide pre-testing, researcher flexibility, prolonged engagement, member checks and peer de-briefing. Methodological coherence was achieved by ensuring compatibility between the research method and data analysis procedures (Morse, Barrett, Mayan, Olson & Spiers, 2002:18). To achieve this, purposive sampling method was employed to enhance the richness of data in an attempt to answer as far as possible the research questions (Russell & Gregory, 2003:36). Prior to conducting interviews, the interview guide was pre-tested with three participants to enhance its reliability. A further approach that was employed to enhance the trustworthiness of the present study was researcher reflexivity. It imposes an obligation on the researcher to disclose all personal beliefs and values that underpin the study, honestly (Creswell & Miller, 2000:121). In the context of this study, the semi-structured nature of the interviews allowed the researcher to be flexible and to approach the study with an objective mind by suppressing inherent preconceptions about the subject under study.
Credibility and trustworthiness were also ensured by assessing the consistency of responses from participants (Brink, 1991:176). Based on this technique, there was evidence of consistency in participants' response and as such, the stability of data was evidenced. As recommended by Kirk and Miller (1986:30-31), the researcher also employed the concept of 'prolonged engagement' with participants through comprehensive interviews. This was done in order to generate a complete data set as well as to enhance the 'thickness' of data with the sole objective of revealing the full picture of the phenomenon under study. In addition, Guba and Lincoln (1989:239) consider member checks as "the single most critical technique for establishing credibility". Five participants that were readily available were requested to inspect the interview transcripts and they vouched that the data represented a true reflection of their views.
The interview transcripts were also subjected to peer-debriefing to enhance credibility (Robson, 1993:404). Peer debriefing was done by two experts in qualitative research and it took the form of an "audit of the decision trail" whereby all stages in the data collection and analysis were scrutinised in order to check their adequacy (Myrdal, 1970:43). The researcher also maintained meticulous documents and presented all the evidence regarding the interviewing process in form of recorded interview transcripts and interview's notes to independent experts as a form of ensuring re-test reliability (Surujlal & Dhurup, 2011:127) and corroborating themes (Crabtree & Miller, 1999:170). Based on the evidence from the interview documents presented, there was consensus between the researcher and the two experts regarding the validity of the themes that emerged from in-depth interviews.

Results and discussion
The depiction of research findings and analysis are closely intertwined in qualitative research. As such, these two sections are integrated in this study to "avoid repetition and to increase readability" (Gustafsson, Hassmen, Kentta & Johansson, 2008:805). In the following sections, the antecedents of the SDT that emerged from the analysis of the sixteen in-depth interviews are discussed. Narratives associated with the antecedents of SDT are provided verbatim from the transcripts.

• Perceived cost
It was evident from the interviews that consumers perceive the purchase of green products as a costly undertaking. Most participants cited price, unavailability of green products in conventional outlets and extraneous effort required to make a green purchase decision as the major impediments. These views are captured in the following excerpts: For me buying green products requires a bit of effort…you can only get these products in upmarket outlets…sometimes I think they are not meant for us ordinary people…you need extra transport money to access them….and making a purchase decision sometimes it's not easy [Oscar].
I regard myself as a price sensitive consumer, price plays a big role in my purchase decisions, honestly I am not prepared to pay for the higher price, which in some cases its double that of non-green products...I believe it's too much…for example the green coffee is twice more expensive than the non-green one... [Melisa].
It can be deduced from the foregoing excerpts that consumers are concerned with the magnitude of physical and cognitive effort required to buy green products. This finding is consistent with that of Gupta and Ogden (2009:389) that showed that the costs of cooperation influence the purchase of green products. Similarly, Hjelmar (2011:341) characterises the green market as a "complex purchase setting" resulting in difficulties in making a green purchase decision.

• Effectiveness of individual behaviour
The majority of the participants perceived that their individual effort appears not enough to address environmental problems. The feelings of inadequacy are captured in the following excerpt: I am willing to participate but I believe my effort alone is not enough. It must be a collective effort...the way I see it our government is not doing enough to punish those companies that are damaging the environment…even if you look at the environmental campaigns by the department of Environmental Affairs…they appear lukewarm. To me they are not stimulating… [Steven].
This finding is in line with that of Shafie and Rennie (2012:365) which revealed that consumers are not equipped to make green product purchase decisions. Steven's comment confirms the association between environmental responsibility and the concept of selfefficacy. Self-efficacy refers to the extent to which individuals believe that their efforts have potential to mitigate the problem at hand (Bandura, 1977:193). Consistent with the selfefficacy concept, Cheah and Phau (2011:459) also found that unless consumers believe that their actions will have the desired outcomes, they are less likely to engage in proenvironmental behaviour.

• Peer influence
The participants also indicated that they are favourably influenced by the views of family members and peers to engage in pro-environmental behaviours. The following narrative indicates the effect of social influence on green purchase behaviour: "When I am at campus my friends influence me much on what to eat…we enjoy buying as a group…it appears our tastes are now converging…but during vacations what to eat appears to be a family decision…whatever you buy it must be acceptable…my mother, in particular likes organic foods…she says they reduce breast cancer and obesity…..so I always buy what is preferred … [Esther].
The foregoing excerpt consolidates the role of family and peer influence in the purchase of green products. This finding reflects those of previous studies by Pickett-Baker and Ozaki (2008:289), and Lockie, Lyons, Lawrence and Grice (2004:145) who found that social environments and peer networks positively influence purchase decisions of green products. Similarly, Lee (2011:303) acknowledges the role of family and peers as socialisation agents with the potential of imparting environmental values and attitudes to their acquaintances. Thus, the uptake of green products is likely to be enhanced if they are promoted through the use of social networks.
• Green dilemma For the majority of the participants, the purchase of green products amounts to a dilemma as they strive to balance individual needs and collective social needs. This view is encapsulated in the following excerpt: I must say I wish to identify with my colleagues on almost everything I do... but sometimes I look at factors that affect me as an individual like my image, style yeah something like that…I always try to make sure that my peers fit in whatever I do though... [Owen].
The foregoing excerpt is supported in literature that characterises the purchase of green products as a social dilemma (Gupta & Odgen, 2009:386). The social dilemma is evident when participants strive to balance the quest for belongingness and self-identity. The need to fit in the social group is supported by the Social Comparison Theory (SCT). The SCT posits that individuals relate their behavioural actions with those of esteemed acquaintances to attest their affiliation (Festinger, 1954:135). Based on the foregoing excerpt, participants tend to compare their product choices with those of their peers.
The preceding narrative also implies that consumers seem to be favourably inclined towards products that bolster their self-image. This is evident when participants strive to buy products that enhance their self-image. This finding is consistent with that of Lee (2008:582) who found that young consumers are favourably inclined towards green products that assuage their self-image. This finding has its theoretical roots in the Self-Image Congruity Theory (SICT) that holds that individuals tend to prefer to buy products that are compatible with their image (Sirgy, 1985:296). Thus, to promote green purchase behaviour among the ego-driven Generation Y consumers, marketers need to strive to align the green product's image with that perceived important by consumers (Hume, 2010:392).

• Perceived trust
The study also revealed that trust plays a major role in promoting and sustaining consumer interest in green products. This view is captured in the following excerpts: …To me benefits of these products to the environment remains a myth…it appears it's a marketing gimmick…I regard it as a ploy to charge higher prices…just like the recent meat labelling scandal….without sound checks on those claims you can't be sure... [Ruth]. …it seems companies just slap a green label to their products…I think the government needs to do more to protect consumers…so honestly I don't trust the so called green products… [Neil].
It can be inferred from the foregoing excerpts that participants demand green marketing messages that are cogently expressed. Notably, an undertone of a deliberate attempt to mislead by marketers is apparent from the preceding excerpts. This finding reiterates the importance of justifying the environmental claims of green products and enhancing the integrity of environmental labels. This finding also dominates green marketing literature and scepticism is considered as the major challenge faced by marketers in promoting the adoption and diffusion of green products (Albayrak, Aksoy & Caber, 2013:36). Additionally, sceptical participants tend to attach more risk to green products as attested by the following excerpt: I buy the products I consider good regularly…green products are relatively new to me...I feel I don't have enough information to consider buying them…because, I have formed a habit of things that I buy all the time, and I'd rather not put in the time and money, and somewhat cost difference for green products… [Owen] It is evident from the foregoing excerpt that perceptions of green-washing tend to erode the formation of favourable attitudes towards green products. This finding tends to endorse the recommendation by Atkinson and Rosenthal (2014:39) that marketers need to structure green marketing messages in a way that fosters consumer trust. Similarly, Young, Hwang, McDonald and Oates (2010:29) also stressed the importance of the role of government in setting clearer regulations to stamp out green-washing claims by consumers.

Limitations and directions for further research
Although the objective of the study was achieved, the findings are prone to limitations that offer avenues for future research. Firstly, the present study utilised non-probability sampling methods that included purposive and convenience sampling to select participants. The study also employed a self-reporting method of data collection that involved the use of in-depth interviews. This increased the chances of the findings to be susceptible to sampling and social desirability bias. Thus, future research efforts may employ probability sampling methods and multiple data collection methods to enhance the external validity of the findings.
Secondly, the results of the study are limited to the Generation Y consumers enrolled at higher education institutions in the Gauteng Province in South Africa. As such, the findings of the study may not adequately capture the influence of the SDT on green purchase behaviour of all Generation Y consumers and other generational cohorts in South Africa. Thus, it would be enlightening to examine the influence of SDT on green purchase behaviour using a broader heterogeneous sample frame to enhance the generalisability of the findings.

Conclusion
The aim of the study was to understand the influence of the SDT on green purchase behaviour of Generation Y consumers. The study identified perceived cost, self-efficacy, trust and peer influence as the main antecedents of SDT that influence green purchase behaviour. Self-efficacy perceptions may be enhanced in consumers through the provision of objective environment knowledge and environmental awareness campaigns (Ling, 2013:14504). Green marketing tools such as environmental labels and rational green product messages have the potential to enhance self-efficacy in Generation Y consumers. Alternatively, marketers may formulate marketing messages that reinforce the importance of individual contribution in preserving the environment.
In order to foster the purchase of green products, it is recommended that the green marketing strategy be focused on setting competitive prices, and enhancing quality and availability of green products relative to non-green products (Chen & Chang, 2012:503). There is also a need to integrate traditional product attributes such as price, quality and availability into the