In 2015, World Health Organization worked with the Nepal Ministry of Health to redesign the country’s Adolescent Sexual and Reproductive Health, through a pilot study utilizing the Innov8 Approach – an 8-step review process geared towards helping health programmes better address gender, equity, human rights and social determinants of health. The aim was to identify the adolescent subpopulations being missed, increase coverages, identify inequities and take a holistic approach to adolescent health and development. Specific barriers experienced by different subpopulations such as distance and cost of travel, inability to come during opening hours, lack of privacy and confidentiality, adverse gender norms, among other factors were uncovered through the pilot. This publication presents the findings, barriers and recommendations from the pilot, which subsequently informed the new National Adolescent Health Program, to ensure that “No one is left behind”. Measures include an increased focus on outreach services (in particular in disadvantaged areas), capacity building of health workers on adolescent-friendly and gender-responsive services, and ensuring that adolescent representatives participate in local decision-making processes on health through enhanced community engagement. The findings further reiterate the need to engage other government sectors, such as education and nutrition, to tackle the causes of early marriage and pregnancy, as well as mental and school health. As national health programmes strive to meet the 2030 Sustainable Development Agenda and the targets set out in the Global Strategy for Women’s, Children’s and Adolescents’ Health, integrating lessons from the Innov8 pilot helped strengthen the national programme’s ability to reach vulnerable adolescents, reduce inequities, and improve the overall health of adolescents in Nepal.