 Third, major challenges remain in evaluating the impact of structural interventions. Few NGO interventions are evaluated rigorously to rule out alternative explanations for success. Perhaps most importantly, few NGO program evaluations involve a control group. Further, most structural intervention assessments are limited to either structural variables on which they directly intervene such as social norms that condone intimate-partner violence or microcredit program use rates or key HIV health outcomes only. These research gaps in the development, implementation and evaluation of structural interventions limit their wider dissemination and scale-up in resource-poor countries, where services are much needed. 