A multi-country operations research study investigating the combined effectiveness of a set of interventions designed to improve adolescent reproductive health (RH) knowledge, attitude and practices was launched in 1999. This study was conducted concurrently in Bangladesh, Kenya, Mexico and Senegal. The principal elements of the project were established through a consultative process that included several of the principal agencies, donors, research organizations and individuals working in the field of adolescent health care internationally. Because of the study’s multi-country nature, there was a degree of standardization built into its design. However, the overall design of the interventions also conformed.