MONETARY INCENTIVES ARE INCREASINGLY used to help motivate survey participation. Research Ethics Committees have begun to ask whether, and under what conditions, the use of monetary incentives to induce participation might be coercive. The article reports research from an online vignette-based study bearing on this question, concluding that at present the evidence suggests that larger incentives do not induce research participants to accept higher risks than they would be unwilling to accept with smaller ones.