The aim of this study was to determine the critical incidents that contribute to the initiation of substance use and abuse among women in Trinidad and Tobago. Twenty women were randomly selected from 46 women currently attending 43 drug rehabilitation centres, Narcotics Anonymous and Alcoholics Anonymous groups in Trinidad and Tobago. In-depth semi-structured interviews using the critical incident technique were conducted. Interviews were recorded, transcribed and analyzed. Concepts, categories and themes were determined by team study and group discussion. The critical incidents that influenced women to initiate the use and abuse of substances fell into eight major themes: factors intrinsic to the individual woman, family factors, social and environmental factors, life stresses, relationship issues, abuse, peer pressure and substance use and abuse as a coping mechanism. The results imply that the factors contributing to the initiation of substance use and abuse among women in Trinidad and Tobago are many and complex. As such any attempt to address this issue requires a broad-based approach. Such an approach should address family use of such substances, societal acceptance of them, availability, the self-esteem of the individual woman and her ability to cope with peer and internal stresses.