Publisher Summary This chapter reviews the results of the investigations of surface topography of suspended cells. It explains surface topography of suspended cultured tissue cells, especially of normal and transformed fibroblasts. Some data about the cells permanently or almost permanently living in a suspended state are reviewed and example about blood cells or the cells of ascites tumors is illustrated. Microextension can be regarded as reversible specializations of cell surface formed with the participation of the cortical cytoskeleton and of the membrane. The data available at present suggest that different types of alterations of cytoskeleton may be involved in the formation of blebs and microvilli. Protrusion of blebs involves partial destruction of cortical network of microfilaments, formation of holes in this network and flow of cytoplasmic content into these holes. Polymerization of actin microfilaments may be the main process leading to the extension of microvilli. The chapter explains the mechanisms of formation of microextension.