Rsp5 is a conserved ubiquitin ligase involved in regulation of numerous cellular processes. A growing number of publications describing new functions of the ligase have appeared in recent years. Rsp5 was shown to be involved in the control of intracellular trafficking of proteins via endocytosis and multivesicular body sorting. Moreover, nuclear functions of Rsp5 in response to various stresses have been discovered. Rsp5 is also involved in the regulation of unsaturated fatty acid and sterol synthesis and phospholipid composition. Here, an overview of Rsp5 functions with emphasis on its involvement in the regulation of lipid biosynthesis will be presented.