Cross et al’s important new article identifies the ‘poor translation of clinical practice guidelines … into clinical practice’ and the need to understand how to close the gap between the production of new evidence and its use in clinical settings.1 They analyse 16 studies that focus on how ‘knowledge brokers’ might help, finding a decidedly mixed picture. While knowledge brokerage involves sensible measures—to generate and share guidelines, engage with relevant stakeholders and build greater capacity to share and adopt guidelines—their effectiveness is only clear in half of the relevant randomised controlled trials (RCTs) (although higher across all studies). Given the small number of relevant studies that the authors found (including relatively few on ‘linkage agent roles’), and the high uncertainty that remains, it is no surprise that they conclude with a call for more research.