In Mexico, due to reduced and unevenly distributed hydrological resources and incipient water management capabilities, climate change adaptation in the water sector is recognized as an urgent issue. To derive lessons for climate change adaptation, this paper evaluates the results gained after five years of an integrated river basin management (IRBM) programme in the Conchos River in northern Mexico. Autonomous adaptation measures assessed include: modernization of irrigation practices; pilot sustainable watershed management projects in the upper basin; development of an environmental flow assessment and a proposal to improve water allocation; and the creation of the Inter-institutional Working Group as a basin organization. These measures have improved river basin management, yet adverse outcomes were also observed, such as impacts of surface water efficiency measures that were not managed in conjunction with groundwater. Key adaptation lessons derived include: the importance of multi-stakeholder participation in designing and implementing adaptive management measures; the need for significant investment in transfer of expertise and capacity building; and the positive effect of linking local, national and international institutions. These results highlight the need for more investment in ‘soft’ adaptive management in place of infrastructure. In the Rio Conchos, if these ‘no regrets’ adaptation measures are consolidated in the following years, they will serve as a foundation to develop planned and more effective climate change adaptation programmes, and enhance institutional, environmental and societal resilience.