ONE of the most useful tissues available to the human geneticist for cell culture is skin. It is plentiful, easy to grow, remains diploid for several months, and can be frozen, stored for probably years, then thawed and re-cultured1. What is needed for large-scale family or population studies is a simple, rapid, relatively painless procedure for obtaining suitable skin biopsies. Just such a procedure, using an electric rotary punch, is described in the literature by Urbach and Shelley2; but few investigators outside the field of dermatology seem to be aware of the technique. We have had such good results with an adaptation of the punch drill that we call attention to it in this communication and present our results to date. The procedure is as rapid and simple as a veni-puncture, and certainly no more painful. No anaesthesia or suture is required, and the biopsy can be performed in the clinic, the office, or the patient's home.