Experience with patch test screening has been analyzed, and a modern patch test screening series presented. The screening series we find useful differs from most other recommended series in emphasizing medicaments and mixtures. While our experience deals only with patients from the western United States, the majority of conclusions should apply to patients elsewhere in North America. The proposed screening series is suggested as a step in the modernization of screening series so as to increase the clinically useful information extracted from routine patch testing. We find patch test screening valuable providing it is used to supplement, and not to supplant, patch testing with suspected environmental agents.