STEP into Action assessed the efficacy of a peer-based HIV prevention intervention in reducing HIV risk behaviors among people who inject drugs (PWIDs) in Baltimore. This analysis examined the effect of the intervention on the change in frequency of conversation about HIV prevention topics over time. 114 participants were randomized into an experimental and 113 into a control group. Data was collected prospectively at 6, 12, and 18 months. The experimental group talked more frequently about HIV prevention topics compared to the control group at 6-month visit. At 18 months relative risk ratios (RRR) remained statistically significant for conversation about the danger of needle sharing (RRR = 3.21) and condom use (RRR = 2.81). The intervention resulted in an increased conversation about HIV prevention among PWIDs, but the sustainability past 6 months remained a challenge; suggesting that interventions should be designed to constantly reinforce communication about HIV prevention among PWIDs.