Background: Rehabilitation programs for criminal offenders target primary outcomes such as effects on criminogenic needs and secondary outcomes of reducing recidivism. Most evaluation studies focus only on one type of outcome. This study evaluated outcomes on both primary and secondary targets of the Reasoning and Rehabilitation (R&R) program for 372 male Swedish prisoners. Method: Short-term changes were measured by the Sense of Coherence scale, Eysenck's Impulsiveness, Venturesomeness and Empathy Questionnaire and the Criminal Sentiments Scale. Long-term changes were measured by reconviction outcomes compared to matched controls. Results: The total program completion rate was 77% over a five-year period. Primary target evaluation showed significant pro-social short-term improvements among program completers in sense of coherence, impulsiveness, venturesomeness, attitudes towards the law, courts and police, tolerance of law violation and criminal identification. Secondary target evaluation by survival analysis showed that program completers had a 25% lower risk of reconviction up to 36 months following prison release, compared to matched controls. Dropouts, who were younger and more criminally active, had a 38% higher comparative risk of reconviction. Significant differences occurred in overall 36-month reconviction rates: 48.1% for program completers (n = 212), 60.3% for controls (n = 451) and 73.4% for dropouts (n = 64). Conclusions: The R&R program was associated with positive short-and long-term results. Future research should expand test batteries to assessment of cognitive and social skill acquisition and measurement of motivation for change, as well as randomizing study participants to investigate a possible selection bias in the present results. (Contains 4 tables and 1 figure.)