This external evaluation examines whether the core component of m2m's Mentor Mother Model -- peer education an psychosocial support services -- improves the uptake of Prevention of Mother-To-Child Transmission (PMTCT) services, as wel as the health and wellbeing of mothers and their infants. It also investigates the cost-benefit of scaling up the Mentor Mother Model nationally in Uganda. To determine this, the study examines the differences in mother and infant uptake of PMTC services and health outcomes, as well as women's psychosocial wellbeing at m2m-supported health facilities compared to similar facilities with no m2m presence (the control sites). The study was conducted across 62 health facilities divided into two groups: 31 intervention sites (with an m2m presence) and 31 control sites (without m2m presence). Approximately 1,150 mother-baby pair records of clients who received PMTCT services between January 2011 and March 2014 were reviewed in each group. Additionally, approximately 400 PMTCT clients in each group who received PMTCT services between June 2012 and March 2014 participated in a survey measuring their psychosocial wellbeing.