Scholars have debated, asserted and posited that the source of homosexuality in both gay men and lesbian women is found either in nature or nurture. Of specific interest to this research was the self-identified source of homosexuality in gay men through their lived experience. A Malaysian-based context was taken due to the growing interest, both politically and socially, of the social phenomenon of homosexuality in Malaysia. As personal experience was the data source selected for this research and social construction of identity was the perspective taken, phenomenology acted as the theoretical underpinning through which the shared experience of the respondents was analysed. The geographic setting of the research was Penang, Malaysia as it was an urban area that had been identified as having a population of self-identified gay men. A qualitative perspective was taken due to the sensitive nature of the research. The sample population was gathered via purposive sampling and the snowball technique and a total of 33 respondents were recruited. All respondents were interviewed in-depth where a semi-structured interview questionnaire was utilised. All data were transcribed and analysed via a content analysis matrix. The findings suggest that the source of homosexuality for the respondents was nature and not nurture. Respondents attribute their homosexuality to genetics, inborn hormonal influence and biology. However, the findings do point out that nurture has a part to play in the development of self-identified gay men as individuals. Nurturing via friendships, role-modelling and environments that are affirming and positive portrayals of homosexuality in the media allow the respondents to internalise positive attitudes towards their homosexuality. Research into the source of homosexuality from the viewpoint of complementarity as opposed to opposition is a direction that would benefit studies of homosexuality. Longitudinal research would deepen understanding of the source of homosexuality.