Approved by the GCF Board at B.43, this synthesis brings together evidence from evaluations, reviews, and stakeholder interviews on GCF's support for REDD+. It synthesizes evidence on the evolution of GCF's support within the global REDD+ and forest-based climate action landscape, highlighting key progress, lessons, and persistent challenges following the mainstreaming of REDD+ results-based payments (RBPs) into GCF's regular programming. The report is scheduled to be completed before B.47.