This book discusses different aspects of neutropenia including drug-induced neutropenia, which is quite common, and neutropenia in chemotherapy-treated patients. The authors offer an all-encompassing approach to the pathobiology and treatment of neutropenic disorders. This book reviews current information concerning neutropenia. There have been significant advances in medicine; however, bacterial infections continue to contribute significantly to morbidity and mortality in patients with neutropenia particularly cancer patients who develop chemotherapy-induced neutropenia. In this setting, it is important to understand pathophysiology of neutropenia and have a logical approach in diagnosis and treatment of neutropenia. Gathering all this information in one book will be of immense benefit for healthcare workers including physicians, pharmacists, physician assistants, nurse practitioners and nurses and this in turn will help them improve the care of their patients. It will also be of benefit for pharmacists as a source of clinical and pharmacological knowledge. For researchers undertaking research in the field of hemato-oncology or pharmacology, this will be a useful starting point for reviewing the literature. The editors have tried to allow information in book chapters to show different aspects and various view points on related issues.