Cancer patients demand a high level of involvement in decisions concerning treatment. Many patients are informed about experimental trials, and especially the first consultation may be crucial for the future communication and treatment process. Patients with nonresectable non-small-cell lung cancer or colorectal cancer informed about experimental chemotherapy completed a questionnaire on satisfaction with the communication process, general attitude towards experimental treatments, the substance of information, and personal contact with the physician following their first consultation in a medical oncology unit. Physicians completed a questionnaire on their perception of the patients' satisfaction. Among 68 physician-cancer patient pairs, 29 patients were informed on chemotherapy in randomised trials and 39 in nonrandomised studies. The general attitude towards experimental treatment was positive or very positive in 71% of patients. Information on the treatment was perceived as completely adequate in 93% of patients informed on randomised and in 67% informed on nonrandomised trials. Physicians underestimated the patients' satisfaction with the overall communication process, the personal contact, the patients' perceived sufficiency of the specific treatment information and their ability to decide on study entry. In conclusion, considerable differences were observed between patients informed about experimental chemotherapy in randomised and nonrandomised trials, both with respect to their perception of how adequate the information on the specific treatments were, and whether it was sufficient for decisions on study entry. This study type effect should be accounted for in future evaluations of communication and patient satisfaction. The data also support the fact that cancer patients have a desire for and ability to understand rather detailed and comprehensive treatment information.