Eighty consecutive patients, with good experience of acupuncture, were questioned about their clinical response to acupuncture. This is classified as immediate, intermediate and therapeutic. The long term therapeutic response was delayed in onset by 3 or more days in 50% of the patients. Most scientific study concentrates on the immediate reactions, so this delay in the therapeutic response is not generally recognised, understood or investigated, nor are the occasional adverse reactions (15% in this study) occuring during the intermediate stage. The response in the immediate and intermediate stages may not be related to the longer term therapeutic effect.