The International Code of Marketing of Breast-milk Substitutes (the Code) adopted by the World Health Assembly (WHA) in 1981 and regularly updated through subsequent WHA resolutions, represents the international policy framework for protecting breastfeeding against inappropriate marketing practices. By March 2016, at least 135 countries had some measures covering provisions of the Code in their legislation. The translation of the International Code into national measures was investigated in the context of the advocacy efforts undertaken by the Alive & Thrive (A&T) initiative with UNICEF and partners. A real-time evaluation was carried out over 22 months in seven Southeast Asian countries (Cambodia, Indonesia, Lao People's Democratic Republic [Lao PDR], Myanmar, Thailand, Vietnam, and Timor-Leste) and two African countries (Burkina Faso and Ethiopia). Drivers of policy change and progress were examined. Two theory-based approaches were used: developmental evaluation and contribution analysis. Data collection methods included participant observation, key informant meetings, in-depth interviews, reflective practice, and desk review. Overall, countries made significant progress in translating the International Code into national measures and in moving forward throughout the policy cycle. The main driver of policy change was the creation of a strategic group, which engaged key relevant actors and supported the government in the performance of 15 critical tasks, which the analysis reveals is a second driver. Those critical tasks are described in this paper and could help public health advocates to anticipate the stages and challenges of policy change and develop more effective strategies to translate the Code into their legal framework.