In developing countries, with minimal resources devoted to mental health, detection and treatment of mental illness necessarily falls to primary care providers, yet research has rarely focused on the experiences of private practitioners, especially in rural areas. This mixed-methods study investigated the diagnosis and treatment of depression by rural Kenyan primary care providers and assessed the impact of a brief training intervention on their comfort level and competence in recognizing depression. Participants were 44 providers practicing in private clinics in rural Kenya randomly assigned to intervention and wait-list control groups. Both groups completed pretest questionnaires eliciting diagnostic hypotheses based on live vignettes. The intervention group received brief training about screening for depression. Two months later, 23 participants returned to complete posttest questionnaires. Results demonstrated that brief training about depression and access to diagnostic instruments increased providers' comfort level with diagnosing depression; treatment preferences and barriers to care were also identified.