Background: Illness Management & Recovery (IMR) is a curriculum-based program for people with severe and persistent mental illness. To date, four randomized controlled trials (RCTs) have been published on it. As these produced mixed results, we conducted a pilot study to test the feasibility of conducting a new RCT in a Dutch psychiatric institute. Because our primary objective was to evaluate support for implementing IMR on a broader scale, we examined participant recruitment, client outcomes, and clients' and clinicians' satisfaction. Secondary objectives were to evaluate fidelity, trainers' training and supervision, and to explore program duration, dropout, and client characteristics related to dropout. For reporting, we used the checklist for pilot studies adopted from the CONSORT Statement. Methods: This program evaluation included a process-evaluation and an outcome evaluation with a One Group Pre-Posttest Design (N = 81). Interviews and internal reports were used to monitor participant numbers, program duration, dropout, and completers' characteristics. Clients' and clinicians' satisfaction and provision of trainers' training and supervision were assessed through interviews. Fidelity was assessed on the IMR Fidelity Scale; client outcomes were assessed on the IMR scale (client and clinician versions) and the Recovery Markers Questionnaire (RMQ). Results: Eighty-one participants were recruited of 167 people who were assessed for eligibility. Completers and clinicians were satisfied, and scores for completers improved significantly on the IMR scale (clinician version) (d = 0.84) and RMQ (d = 0.52), and not significantly on the IMR scale client version (d = 0.41). Mean fidelity was good, but three groups had only moderate fidelity. Our feasibility criterion for trainers' education and supervision was partly attained. Dropout from treatment was 51 %; female participants and people who scored higher on both IMR-scales at baseline had a significantly lower chance of dropping out. The duration of IMR varied ...