A series of disconnected early observations on anther and pollen development in angiosperms led to the discovery that male function can be selectively abolished by gene action at any time from the stage of initiation of the anther primordium to the stage of pollen maturation. Occasionally, male function is inhibited nongenetically by chemical or environmental manipulations of the flower. Irrespective of the means of interfering with sex expression, phenotypically this results in the generation of male steriles or plants that fail to produce anthers with viable pollen grains, combined with side effects on other aspects of anther development. Since sterility interferes almost solely with anther and pollen developmental episodes, its study may assist in the analysis of gene expression during male sporogenesis and gametogenesis. For, if we cannot discern the reasons for the abnormal development of pollen grains, we will be sorely limited in our efforts to understand the molecular basis for their normal development. From a practical point of view, male sterility is akin to self-emasculation of the flower, so an understanding of the mechanism involved in pollen degeneration could have important ramifications in breeding programs and in the production of hybrid seeds without the need for labor-intensive procedures.