Lung cancer is the most common and most lethal malignancy worldwide, causing 1.4 million diseases every year. Half of non-small cell lung cancers (NSCLC) are diagnosed at such an advanced stage that a cure cannot be considered a realistic aim, and over 75% of cases selected for a curative treatment eventually relapse within five years. The 5-year overall survival rates are less than 20% for NSCLC patients. As a disease, NSCLC demands our maximum abilities as researchers, physicians, and care-givers, and a continuous updating of our knowledge. Conventional chemotherapy for advanced NSCLC does not provide a great long-term benefit in terms of survival. Accordingly, a different therapeutic approach has to be explored. The human epidermal growth factor family of surface receptors (HER) became a critical target to be investigated. The epidermal growth factor receptor (EGFR) is overexpressed in over 80% of non-small cell lung cancer. The presence of sensitizing conformational mutations in the EGFR increases the efficacy of modern tyrosine kinase inhibitors against its inner portion (EGFR-TKI). The EGFR-TKIs greatly prolong disease-free survival of those patients harboring sensitizing EGFR mutations, and have been suggested as an essential tool in the therapeutic repertoire. This volume aims to serve as an updated compendium of biology and applications of anti-EGFR therapies, and offers a look at the future of anti-HER therapy in lung cancer. This volume exhaustively reviews and discusses: 1) the nature and significance of activating EGFR mutations, and those clinical and pathological phenomena related to HER alterations; 2) the most common laboratory methodologies to study EGFR, and the future of HER analysis; 3) the right time to analyze EGFR mutations and evolutionary changes in the HER; 4) EGFR-TKI application in unselected and selected NSCLC patients; 5) upcoming anti-HER therapies; 6) the eventual role of anti-HER therapies in early NSCLC; 7) mechanisms of acquired resistance to anti-HER therapies, and experimental and conventional strategies to bypass them; 8) the application of anti-HER therapies in other malignancies. This book is an indispensable handbook for all those specialists devoted to the diagnosis and management of lung cancer.