Policy and practice decisions should be informed by the best available research evidence. However, there is much confusion over what ‘rigorous evidence’ looks like. In health, robust systems have been designed to collate, synthesise and translate evidence from primary studies to practical guidelines. In the field of environment, however, this process is lagging behind due to a lack of awareness of and appreciation and capacity for rigorous evidence synthesis. In this talk, I will introduce the concept of systematic reviews and maps, and the global organisations that aim to support systematic review authors and those in need of robust evidence.