This paper reviews three UK-based welfare-to-work programmes featuring time-limited financial incentives to leave out-of-work benefits for employment. The policies considered are (i) the Employment Retention and Advancement demonstration, aimed at lone parents and the long-term unemployed; (ii) In-Work Credit, aimed at lone parents on welfare; (iii) Pathways to Work, aimed at recipients of incapacity benefits. I illustrate the difficulties in extrapolating from specific findings to general policy-relevant conclusions. Finally, I depict the challenge facing evaluators in future and point to the directions in which evaluation will need to develop if it is to contribute more fully to policy-relevant evaluation.