Depression is a mental illness in which a person experiences deep unshakeable sadness and a lack of interest in nearly all activities. Research highlights the enormity of the problem. It is reported that one hundred million people worldwide develop clinically significant depression every year. A single major cause of depression has not been identified. Reasons for the illness may be linked to genetic, biological, social and psychological factors. This research project aims to look at the effects of these causes of depression on men and women. An equal number of male and female trainee psychotherapists participated in this study. The participants were chosen. for convenient and purposive reasons. This study availed of a qualitative approach using a questionnaire and semi-structured interviews to gather data. The main findings of this study confirm previous research on depression and gender. This study identified the prevalence of work problems as a cause of depression. The findings of this study reveal that the family environment inhibited expression of emotion in both sexes. It also highlights that this experience affected men and women's ability to express feelings during their depression. This study concludes that the causes of depression do not operate in isolation. It is suggested therefore that the biological, social and psychological causes of depression come together in affecting men and women's experience of the illness.