Advanced patch technology has yielded a novel transdermal therapeutic system (TDS) for the rate-controlled systemic delivery of buprenorphine. Buprenorphine TDS is available in three strengths with release rates of 35, 52.5 and 70 mug/h over 72 h, corresponding to daily doses of 0.8, 1.2 and 1.6 mg, respectively. In total, 445 patients with chronic pain of malignant or nonmalignant origin requiring long-term treatment with potent opioid analgesics were enrolled in the clinical trial programme. The patients were treated with buprenorphine TDS in one of three dosage strengths or with placebo TDS in a randomised double-blind setting. Greater pain relief was documented in patients treated with buprenorphine TDS than in those treated with placebo. The benefit of buprenorphine TDS was further reflected in the larger number of patients who slept for longer than 6 h per night. Patients switching from Step 2 or Step 3 opioids to buprenorphine TDS encountered no problems with the conversion. Typical opioid-related adverse events were reported with a low incidence and mild intensity. In an open follow-up study 239 patients elected to continue treatment with buprenorphine TDS. The confirmation of clinical benefit, coupled with a high level of patient compliance and improved quality of life, substantiate the usefulness of buprenorphine TDS in a practical setting.