Abstract
In spite of its long history and widespread use, acupuncture has failed to demonstrate its clinical effectiveness convincingly. This article is aimed at discussing some of the problems related to acupuncture research that might have contributed to this overt discrepancy. These are the effects of investigator bias, the abundance of derivatives of traditional acupuncture, the lack of standardisation of treatment and selection of acupoints, and the difficulty in blinding the investigator, patient or therapist, as well as the problems related to the choice of an appropriate placebo. Such, mostly methodological difficulties, can and must be overcome if the controversy regarding the clinical effectiveness of acupuncture is to be solved.