Book excerpt: This third edition is the product of the author’s 25 years of experience with flow cytometry; although it covers the wide spectrum of hematopoietic tumors, the focus remains on most important clinical diagnoses, such as acute promyelocytic leukemia, identification of blasts, identification of clonal B-cell population, differentiating mature versus immature T-cell proliferations, deferential diagnosis between hematogones and B-ALL or distinction between chronic and acute monocytic proliferations. All hematopathologists and neoplastic hematologists will find this an important resource for keeping up to date with developments in clinical practice.