Stamens are the male reproductive organs of angiosperms, and their proper development ensures male fertility and crop productivity. In addition, male sterile varieties are important for hybrid breeding and increased crop yield. Therefore, it is highly important for both basic plant development and crop breeding to understand the regulatory mechanisms of stamen development. Within the stamen, the anther contains reproductive cells and the surrounding somatic cells that support the formation and development of reproductive cells. The major developmental events and morphological changes of the anther are similar among different angiosperm species, including the establishment of anther polarity, anther morphogenesis to form the characteristic butterfly-like morphology of the cross section, meiosis to produce haploid microspores, pollen development, and release from the anther. There are great interests in investigating the molecular mechanisms underlying these processes using molecular genetics and cell biological approaches. In recent decades, breakthroughs have been made in understanding anther developmental processes due to the rapid advances in transcriptome sequencing, quantitative mass spectrometry, and microscopic technologies. This chapter presents a brief description of anther development and a detailed overview of advances in understanding the mechanisms underlying anther development in flowering plants, especially in model species such as Arabidopsis, rice, and maize. The emphasis here is on gene functions and molecular interactions, including feedback regulatory loops in both cell signaling and transcriptional control that are crucial for anther initiation, cell type specification, and tapetum development and function.