The unique reactivity of hypervalent iodine reagents with Pd-0 and Pd-II complexes has been exploited for a variety of synthetically useful organic transformations. For example, I-III reagents have been used in place of aryl halides for diverse Pd-catalyzed C-C and C-heteroatom bond-forming cross-coupling reactions. In addition, these reagents have found application in Pd-catalyzed oxidation reactions, including the oxidative functionalization of C-H bonds and the 1,2-aminooxygenation of olefinic substrates. This review discusses both the synthetic utility and the interesting mechanistic features of these transformations.