As climate change impacts are felt within growing numbers of cities in low- and middle-income countries, there is growing interest in the adaptation plans and programmes put forward by city authorities. Yet cities face considerable constraints on this front. This paper aims to provide a better understanding of these constraints by analyzing the case of Rosario, in Argentina. The city has a strong coherent governance system, with a commitment to decentralization, transparency, accountability and participation. Its long tradition of urban planning has evolved to include a broad vision of urban challenges and responses, a commitment to environmental sustainability and a strategic plan that has involved multiple stakeholders. This paper describes the many measures implemented in Rosario over the last 18 years, which provide a solid foundation for more systematically addressing adaptation. It also describes the significant challenges faced by the city’s administration, especially around funding, data and the challenge of responding to pressing and competing interests.