: findings from the formative research to inform the initiative "Reaching those most left behind through comprehensive sexuality education for out-of-school young people" in Colombia.

This paper presents the results of formative research conducted from January to June 2020 in the Department of Atlántico, Caribbean region of Colombia, whose findings were used as inputs to design the national strategy for comprehensive sexuality education (CSE) outside school - - including its curriculum. This is within the framework of the multi-country project coordinated by UNFPA and WHO aimed at generating evidence on the role of facilitators in the delivery of CSE in non-school contexts. The research was carried out in four municipalities in northern Colombia, in rural and marginal urban contexts with conditions of vulnerability for the adolescent population, including a strong presence of migrant populations from Venezuela.