Two examples of the growing literature by political scientists on the substantial changes which have taken place within Congress and in the relationship of Congress to the Executive since the 1960s. The Mann-Ornstein volume is by far the better: the research is deeper, the writing better, and the context broader. The Abshire-Nurnberger book, focusing more narrowly on Congress vs. the President, has been somewhat overtaken by events, as the editors themselves implicitly admit.