A comprehensive review of reagents used for the chemical modification of proteins, the fourth edition represents a major revision. The completely updated text is substantially larger and includes five new chapters: Alkylating Agents, Acylating Agents, Nitration and Nitrosylation, Oxidation, and Modification of Proteins with Reducing Agents. The format has been markedly revised, presenting information based on the chemical nature of the modifying material and on the amino acid residue modified. Much of the information is in tabular form to enable the rapid location of cited material.