Zoos and aquariums have shifted their focus over recent years, taking a much more active role in wildlife conservation and in promoting conservation learning among their visitors. Research in these settings provides a valuable foundation for the emerging field of non-captive wildlife tourism. In particular, valuable lessons regarding the potential impact of wildlife encounters on visitors' conservation attitudes and behaviour can be drawn from research in zoos and aquariums. This paper explores those aspects of wildlife encounters that appear to contribute most to conservation learning. These include observing animals in their "natural" environment; opportunities for close encounters with wildlife; opportunities to observe animal behaviour; engaging visitors emotionally; connecting with visitors' prior knowledge and experiences; using persuasive communication; linking conservation goals and everyday actions; and providing incentives and activities to support visitors' behaviour change. The extent to which wildlife tourists may be receptive to conservation messages is also considered, in light of research in zoos and aquariums. The implications of these findings for conservation learning in the context of non-captive wildlife tourism are discussed and suggestions for future research in this area are made. Several methodological challenges facing the field are also discussed.