This study examined the role of stress as a mediator of the relationship between prior drug addiction and current high-risk sexual behaviour. Eight hundred twenty women aged 18 to 30years, who received care at community-based family planning clinics, were interviewed using the Composite International Diagnostic Interview and the Sexual Risk Behavior Assessment Schedule. They also completed the brief version of the Self-Control Scale as a measure of problem-solving strategies and measures of recent stressful events, daily hassles and ongoing chronic stress. Regardless of addiction history, stress exposure during the previous 12months was associated with risky sexual behaviour during the previous 12months. Structural equation modelling revealed that 12-month stress levels mediated the relationship between past drug addiction and 12-month high-risk sexual behaviours, as well as the negative relationship between problem-solving strategies and high-risk sexual behaviours. Problem-solving strategies did not moderate the relationship between drug addiction and high-risk sexual behaviours. These findings suggest that stress management training may help reduce risky behaviour among young, low-income women Copyright (c) 2014 John Wiley & Sons, Ltd.