The volumes that have appeared in the three years since BIOMEMBRANES was launched illustrate the kinds of in­ formation the editor and the publishers envisaged would constitute the series. Some, such as this one, would consist of scholarly reviews of specialized topics; some, such as Volumes 2 and 3, would be the published chronicles of conferences; and others, such as Volumes 4 and 6, would be specialized monographs. In this way, we have hoped to provide not only reasoned critical opinions but also ideas "hot off the press. " Whether or not the views articulated ultimately stand the test of time is not as important as that their dissemination to the scientific community provides that unique stimulation that only flows from the interchange of ideas. This volumes includes chapters on a number of different topics. Rosenthal and Rosenstreich have reviewed the accumu­ lated evidence associating a visible structure of T lymphocytes, the Uropod, with immunologic "activation. " This is the first of many articles that will appear which associates the immune response with membrane function. A current example of Wallach's ability to approach a problem in a unique and original manner is contained in his review of the effects of ionizing radiation on membranes. Dale Oxender has been active in the study of transport for many years. His review is a careful documentary of the properties of specific binding proteins of bacteria and his thesis that these proteins are part of the active transport systems.