This paper examines Michelle Bachelet’s first presidency between 2006-2010. It focuses in particular on the efforts of Chile’s first female president to introduce progressive change and the constraints that she faced in a context where both formal and informal political institutions could act as barriers to change. This paper uses an approach informed by institutional analysis and feminist institutionalism in particular, to explore the extent to which Bachelet could create new institutions and rules or tried to interpret and enact existing rules in new ways to try to bring about change. It focuses on a number of areas. First it examines the political arena looking for example at Bachelet’s efforts to create parity cabinets as well as her relationship with congress and the political parties. Second, it examines the bureaucratic arena, focusing on the policymaking process and on the role of SERNAM, the women’s policy agency. Third, it explores attempts at policy change in a range of areas such as reproductive rights as well as pensions and health. On the assumption that Bachelet will be elected on December 15 2013, the paper will end by speculating on the extent to which the formal and informal institutional constraints have altered in her second term. This in-depth case study will help us to understand the broader challenges and opportunities that women in executive office can face, thus enabling us to understand more clearly the gendered dimensions of executive office.