Stickleback behavior is often cited as an archetypal example of cooperative behavior during predator inspection. Fish from three sites differing in predation risk inspected a model predator in pairs and reciprocated both cooperative moves and defections by the partner, but not on every opportunity. Sticklebacks that originated in the two sites containing piscivorous fish were more likely to reciprocate following a cooperative move than following a defection. Individuals from higher-risk sites were generally more cooperative. Individuals accompanied by a model companion show reciprocal moves of cooperation and defection in response to the model's movements about a third of the time. Both examples of stickleback behavior demonstrate the elements of a strategy of cooperation that may resemble tit-for-tat.