Young people between the ages of 10 and 19 make up 23% of Pakistan's population. In Pakistan, young people face many challenges in terms of sexual and reproductive health (SRH) issues. These include early marriage and pregnancy, low use of contraception, use of unsafe abortion, lack of relevant information and poor knowledge about bodily development including puberty and menstruation, sexuality, reproduction and HIV. This paper examines the scale-up of a rights-based, life skills-based education programme during the period from 2004 until 2013, which included comprehensive education about SRH issues. The programme was introduced by Rutgers WPF Pakistan in a total of 1188 schools. Introduction and scale-up were made possible by a combination of attributes among the organisations leading the development of the programme and the users. The main challenge, which related to the conservative operating environment in which the programme was first introduced, was addressed through a multiplicity of media and advocacy activities in the community, among parents, and by involving teachers, school administrators, district education departments and Muslim scholars in the development and review of the curriculum. The scale-up of a comprehensive sexuality education programme that targets young people in a conservative Muslim country is possible when there is careful curriculum design and materials and approaches are developed in close collaboration with key stakeholders.