This document summarizes the work of GWP CAM in building legitimacy and mandate through partnerships in Central America to address climate change through integrated water resources management and boost national development. Key points include: 1) GWP CAM has worked closely with regional political bodies like SICA and CCAD since 2000 and signed MoUs to coordinate on issues like climate change adaptation. 2) National partnerships have also been built with water directorates and development banks to mainstream climate adaptation and IWRM. 3) Recent steps include joint work on a program concept note, capacity building, and engaging water and climate change officials to strengthen coordination and policymaking. 4) Lessons indicate that developing