Context greatly influences our decisions more than we realize. This document discusses how contextual factors like media environment, time of day, location, and editorial relevance can boost the effectiveness of advertising. Research from campaigns on the Guardian website found that ads placed in a contextually relevant editorial environment saw uplifts of 11-25% in perceived benefit, appeal, and positive feelings toward the advertiser compared to non-relevant contexts. Different categories benefited most from relevance context, such as travel ads seeing 40% greater appeal. Contextual relevance also boosted ad perceptions in print editions of the Guardian and Observer.