The understanding of functional groups is the key to understanding organic chemistry. In the tradition of Patai's Chemistry of Functional Groups each volume treats all aspects of functional groups, touching on theoretical, analytical, synthetic, biological, and industrial aspects. Hypervalent halogen compounds, in particular iodine compounds, are very efficient and selective oxidants which tolerate a wide range of functional groups. The electrophilic properties of these reagents can also be used to introduce other functionalizations. The present volume is the first in the series to survey the properties and chemical behaviour of hypervalent iodine and bromine, their use in organic synthesis, as well as their industrial application. As with all new volumes, the chapters are first published online in Patai's Chemistry of Functional Groups. Once a volume is completed online, it is then published in print format. The printed book offers the traditional quality of the Patai Book Series, complete with an extensive index.