Ongoing antiretroviral therapy (ART) adherence and secondary HIV transmission-risk reduction (positive prevention) support are needed in resource-limited settings. We evaluated a nurse-delivered counseling intervention in Kenya. We trained 90 nurses on a brief counseling algorithm that comprised ART and sexual-risk assessment, risk-reduction messages, and health-promotion planning. Self-reported measures were assessed before, immediately after, and 2 months post-training. Consistent ART adherence assessment was reported by 29% of nurses at baseline and 66% at 2 months post-training ( p < .001). Assessment of patient sexual behaviors was 25% at baseline and 60% at 2 months post-training ( p < .001). Nurse practice behaviors recommended in the counseling algorithm improved significantly at 2 months post-training compared with baseline, odds ratios 4.30–10.50. We found that training nurses in clinical counseling for ART adherence and positive prevention is feasible. Future studies should test impact of nurse counseling on patient outcomes in resource-limited settings.