In 2005, World Vision International designed a longitudinal operations research (OR) project to assess the effectiveness and impact of the three core HIV models (Channels of Hope, Community Care Coalition and Values-based HIV life-skills for children). This OR was implemented in two World Vision area development programmes (ADPs) in Uganda and Zambia. Each ADP had two study sites: intervention and comparison. This paper presents a summary of key findings focused on the CoH model.