Clinical trials demand that investigators pursue absolute truthfulness and objectivity and that they report only honest data. Medical ethics demand that the investigators be in a state of genuine uncertainty regarding the comparative merits of the test and control treatments. Bias, misconduct, and mispresentation in clinical trials are prevalent worldwide. In addition to the universal problems of conducting clinical trials, in Taiwan clinical trials face a number of limitations, including: 1. Lack of qualified, competent clinical investigators, 2. Underpayment of health care providers resulting in poor quality medical service and clinical assessments, 3. Difficulty in recruiting cooperative, compliant patients, 4. Interference with traditional herbal medicines, 5. Criminal penalties for damage incurred during medical care, 6. A no-fault compensation law demanding safety assurance of medical service, 7. Inadequate financial support by local pharmaceutical companies with few assets and intolerance to negative results, 8. A traditional Confucianism doctrine deemed unethical to expose the flaws of the people, and 9. Patronage of traditional herbal medicine out of nationalism. In conclusion, clinical trials in Taiwan are at risk of criminal penalties, are frequently poorly conducted and controlled, and are inadequately scrutinized. As a result, it is extremely difficult to generate high quality clinical trials in Taiwan. © 1997, Drug Information Association. All rights reserved.