Work on global mental health and on the global burden of disease has documented the immense gap between mental health need and mental health services. Three-quarters of the burden of mental disorders occurs in low-and middle-income countries, yet these countries are the least able to respond effectively to address these disorders. 1 In many parts of the world, this gap between mental health needs and available services exceeds 70%; in very-low-income countries this figure is closer to 90%. 1 One strategy for addressing this problem has received considerable attention: the crafting of psychological interventions that can be taught to lay health care workers in low-and middle-income societies.In this issue of JAMA, 2 randomized clinical trials (RCTs)-one from war-affected Pakistan 2 and the other from Zimbabwe 3 -evaluated the effectiveness of this strategy. These trials were conducted by internationally recognized contributors to this field and exemplify the increasing commitment to sustained, scientifically rigorous research on effective, implementable methods for alleviating the substantial mental health burden in resource-poor societies.The trial by Rahman et al 2 compared the effect of 5 weeks of manualized, multidimensional behavioral intervention vs enhanced usual care for symptoms of depression and anxiety, with the intervention delivered by lay health workers in 3 primary care clinics in Peshawar, Pakistan. The trial included 346 adults (mean age, 33 years; range, 18-60 years, 80% women, and 60% with no formal education) allocated randomly in a 1:1 ratio to the 2 trial groups. The intervention included evidence-based problem-solving and behavioral methods provided in individual 90-minute weekly sessions. The guiding approach was viewed as "transdiagnostic," ie, it addressed symptoms occurring across a variety of conditions rather than symptoms pathognomonic of a particular disorder. The primary outcome measures were scores on the continuous Hospital Anxiety and Depression Scale (HADS) 4 overall and the HADS anxiety and depression subscales, assessed at 3 months after start of treatment.The cluster randomized trial by Chibanda et al, 3 conducted in Harare, Zimbabwe, compared the effect of a manualized multimodality intervention vs enhanced usual care for symptoms of common mental disorders with treatment delivered in 6 weekly sessions by lay health workers in 24 primary care clinics. This trial included 573 adults (median age, 33 years; 86% women, 50% had completed primary education, and 42% were HIV positive). The clinics were allo-16. Patel V, Weobong B, Nadkarni A, et al. The effectiveness and cost-effectiveness of lay counsellor-delivered psychological treatments for harmful and dependent drinking and moderate to severe depression in primary care in India: PREMIUM study protocol for randomized controlled trials. Trials. 2014;15:101-110.