Flow cytometry plays a critical role in the diagnosis of hematopoietic neoplasms. Understanding the key immunophenotypic features of each entity is essential for accurate diagnosis. Filling a crucial gap in current literature, this is a comprehensive reference text that systematically details these immunophenotypic profiles. Grounded in real-world experience, this practice-driven resource offers expert guidance on the use of flow cytometry in the diagnosis and classification of hematolymphoid neoplasms. Covering major disease categories, technical insights, and emerging therapies like CAR T-cells, readers will gain a solid foundation for identifying deviations seen in hematologic malignancies, thereby enhancing diagnostic accuracy. Each chapter concludes with key points and diagnostic pitfalls for efficient comprehension and retention. This is an essential tool for pathologists, hematologists, trainees, and laboratory professionals seeking clarity and confidence in diagnosis.