Welfare-to-work programmes promoting employment of people with a disability or chronic illness are an expanding aspect of welfare reform in the UK. What evidence is there of impact on employment outcomes? This paper presents a systematic review of the evidence on UK policy initiatives. Both quantitative and qualitative studies were identified: 5399 abstracts were located, from which 16 studies were critically appraised. Overall, each of the five main welfare-to-work strategies operating in the 1990s helped people with disabilities into work, who were previously on benefits. The proportion of participants gaining employment after involvement ranged from 11% to 50%, dependent on characteristics of participants, such as 'job-readiness', as well as wider labour market context. As most studies were uncontrolled, it was difficult to determine if the improved employment chances were due to the effectiveness of the welfare-to-work interventions themselves or to external factors. Wider impact, such as uptake of schemes as a proportion of the total target population, was weak. The qualitative components identified barriers and facilitators concerned with effective implementation, to aid design of future initiatives.