Against a backdrop of high levels of drug related harms in Scotland, this research aimed to inform training development to aid the upskilling of the workforce to support people who use drugs and are involved in transactional sex. Sixteen qualitative interviews were conducted with participants recruited across four health board areas and a range of services covering sexual health and/or harm reduction. Interviews explored initiation, frequency, and the nature of transactional sex; drug use, and experience of services. A thematic analysis was undertaken. Vulnerability was a key emerging theme when discussing drug use, sexual behavior, and service use. Vulnerability increased risk of a range of harms from sexual assault to injecting harms and overdose. Participants were often, but not always, introduced to drugs and transactional sex by someone who had power over them or was more experienced in drug use and/or sex. High risk drug use was evident in terms of polydrug use, consuming large quantities of drugs, sharing crack pipes/injecting equipment. There is a need for information and services to reduce the risk of harm from drugs, sexual violence, and unprotected sex as well as non-judgmental, trauma aware services. The workforce needs to be skilled to recognize and manage these potentially complex syndemics.