In addition to the process variables, the quality of the powder metallurgical products depends to a large extent on the materials, bulk properties and morphological characteristics of the powders. Material characteristics are relatively well established but the same is not the case with the other two variables because unequivocal definitions of some of the morphological characteristics like particle shape, size and texture on which the bulk properties are strongly depended are yet to be evolved. Among the morphological characteristics, particle shape, though one of the most investigated area remains the least understood. In spite of the complexity of the problem, the necessity for obtaining a better insight of concerned branches in which powders are extensively used have yielded many dimensional and dimensionless parameters for characterizing the powders based on particles shape. The present paper classifies the available literature on the particle shape into four main categories, briefly describes their salient features, critically assesses the merits and demerits of each class and thus makes the perspective more clear for proper and judicious application of one or more methods, of course, depending on the level of accuracy required for charactering the powders. © 1996, Hosokawa Powder Technology Foundation. All rights reserved.