A multimedia program (MMP) was developed to educate patients with prostate cancer about their disease. A within-subjects design was used to investigate the changes in levels of cancer-related knowledge, psychosocial functioning, treatment decision-making role and information needs immediately after browsing the MMP. The participants were 67 men recently diagnosed with prostate cancer. Psychosocial functioning was assessed with 20 items describing common emotional states and coping strategies employed by cancer patients. Treatment decision-making role was assessed with the Control Preference Scale. A principle component analysis of the 20 psychosocial items yielded three components: distress, positive approach and nonacceptance. After browsing the MMP significant increases in knowledge and reductions in distress were reported. Marital status was significantly associated with knowledge gain. Married men and those attending the study session with their spouse displayed a significant shift towards a more active role in treatment decisions. The majority of information needs were fulfilled by the MMP; however, information related to the likelihood of a cure, treatment side effects, coping strategies and aetiology were not completely satisfied by the MMP. Implications of the findings and suggestions for future work on the design and evaluation of the MMP are discussed.