A comprehensive collection of optimized methods for dissecting the mechanisms that control epidermal growth factors (EGF) and their regulators in both normal and pathological states. These readily reproducible techniques range from the study of purified EGF receptor to complex signaling and processing networks in intact cells, including a chapter on the clinical and pharmacological considerations of their use in cancer therapy. The protocols follow the successful Methods in Molecular Biology (TM) series format, each offering step-by-step laboratory instructions, an introduction outlining the principles behind the technique, lists of the necessary equipment and reagents, and tips on troubleshooting and avoiding known pitfalls.