The mouse has become a standard laboratory model organism, particularly for the study of hematopoiesis, the immune system, and inflammation. Although laboratories studying stem cells, blood, and blood-forming tissues have assimilated many new molecular diagnostic methods, the identification of cell lineages through classical light microscopic techniques is often poorly understood and practiced. Mouse Hematology presents a concise review of conventional methods for the preparation, enumeration, and microscopic examination of blood and blood-forming tissues of the laboratory mouse. Along with a short laboratory manual featuring detailed protocols, Mouse Hematology includes a DVD of short video demonstrations of the techniques and a poster of blood cell types for easy identification at the microscope. These rapid, inexpensive assessments can save valuable time and resources essential to the design, development, and interpretation of experiments.