Adolescence is a period marked by rapid physical, cognitive, social, emotional and sexual development. Globally, leading causes of death among adolescents include road injury, HIV, suicide, lower respiratory infections and interpersonal violence. The most common causes of years lost to disability (YLD) include unipolar depressive disorders, iron deficiency anemia, asthma, back and neck pain, anxiety disorders, and in older male adolescents, alcohol use disorders. There are gender and regional differences in the causes of morbidity and mortality in adolescents including in the African region which has the highest rates of disability-adjusted life years lost among adolescents. Globally adolescent pregnancy and childbirth is declining alongside increases in school participation, demand for contraception and age at first marriage. However, in parts of West Africa, rates remain unacceptably high, given the medical and social risks and complications of early pregnancy and childbirth. Therefore, apart from mental health; sexual and reproductive health is a priority concern for adolescent health and wellbeing interventions in West Africa. We aim to generate evidence to inform country and sub-regional level policy advocacy, priority setting, implementation (and de-implementation) for improved adolescent mental, sexual and reproductive health and wellbeing in West Africa. Our principal research question is: "what and why are adolescent wellbeing policy and program priorities in countries in West Africa, what mental, sexual and reproductive health services are available at primary health care level (sub-district /health centers and community) for adolescent health and wellbeing; are they proven effective, what and why are the mechanisms by which these services are funded and how efficiently are available resources used to deliver these services". In the context of these question our research objectives are to: (1) Map and analyze country and sub-regional actors and their ideas, ideology, interests and power, priorities and institutional environment /contexts and decision making in relation to adolescent health and wellbeing policies and programs in West Africa; which policies and priorities are moved into implementation (or not) and why. (2) Analyze sub-district and community level decision making processes of prioritizing which services to deliver and finding and allocating available resources at primary care level to provide adolescents health and wellbeing services (3) Synthesize the existing evidence on the proven effectiveness (or otherwise) of policy priorities and programs related to mental, sexual and reproductive adolescent health and wellbeing being implemented and generate evidence to support implementation and de-implementation (4) Describe the amounts of resources allocated to the various components of primary care mental, sexual and reproductive service provision for adolescent health and wellbeing at sub-district and primary health centers. (5) Assess the effectiveness, and technical efficiencies of available primary health centers in providing adolescents' mental, sexual and reproductive health services. (6) Analyze the factors that explain the technical efficiencies observed in primary health centers in providing Adolescents mental, sexual and reproductive health services. Our study design is a multi-country case study in three selected countries: Ghana (Anglophone) and Niger and Burkina Faso (Francophone). Data collection and analysis will involve qualitative and quantitative methods across a mix of public health disciplines relevant to the questions we are asking; specifically policy analysis, health economics, sociology and anthropology. Our findings will help to inform recommendations as to how primary care mental, sexual and reproductive health services can be configured to better respond to the needs of adolescents' in West Africa.