The Guideline for Isolation Precautions in Hospitals contains many important changes from previous editions of the manual Isolation Techniques for Use in Hospitals:1. Rather than recommending only an isolation system based on categories of isolation, we have included an alternative system: disease-specific isolation precautions. For the first time, hospitals can choose one of these alternative systems for isolation—or they can, of course, design their own system. Some hospitals may prefer to continue using the more familiar, convenient, and simple category-specific isolation precautions. Disease-specific isolation precautions, however, may be more economical, in that only the particular precautions to interrupt transmission of the specific disease are recommended, so time and materials are not spent on unnecessary precautions. With disease-specific isolation precautions, we recommend using a single instruction card on which the need for specific precautions can be shown by checking appropriate items and filling in blanks. When isolation categories are used, we still recommend using standard color-coded category-specific instruction cards; however, the colors have been changed and the cards have been revised to correspond to changes made in the category-specific recommendations.2. Major changes have been made in the titles of and specifications for categories of isolation and the diseases or conditions requiring specific categories of isolation.a. We have retained 3 categories of isolation (Strict Isolation, Respiratory Isolation, and Enteric Precautions) with modifications. We have substantially modified Enteric Precautions to minimize unnecessary use of gowns and gloves. This modification has permitted infections formerly under Excretion Precautions to be combined with those under Enteric Precautions. We have added and deleted diseases from Strict Isolation and Respiratory Isolation.