In recent decades, reports of population blooms of the freshwater jellyfish Craspedacusta sowerbii have become more frequent in lakes across the North Temperate Zone of North America. This exotic invasive species, originally from China, is just one of many to invade lakes in Québec. This article reviews and summarizes information about the species obtained from a wide variety of sources, providing information on its taxonomy, life history, physiology and reproduction. The environmental factors thought to influence its distribution and population size are also discussed, as are the potential effects of its various life stages on lake food webs. This information should provide a clearer understanding of this species, which is being increasingly reported across the province of Québec.