Internists interested in pathology will be amply repaid by reading some of the nine chapters in the present Modern Trends. The analysis of inflammation and repair by Curran of Birmingham, England, is masterful, and an interesting essay by Robertson of London concerns geographic differences in atherosclerosis. Tissue transplantation immunity as discussed by K. A. Porter and the thymic relationship to cancer reviewed by J. F. A. P. Miller are more difficult to understand, possibly because these subjects are less well defined. Physicians interested in updating their knowledge of electron microscopy will profit from the article on the liver by Schaffner and Popper of New York. Four additional more technical chapters on advances in pathology complete the volume.