Hydrops fetalis is a complex and fascinating disorder. This article explains the characteristics of each type of hydrops fetalis, immune and non-immune. The etiology and the associated underlying conditions leading to the development of these disorders are also discussed. The ultrasonographic appearance of a classic case of hydrops fetalis is described including variations in its appearance and its numerous differential diagnoses. Several causes of non-immune hydrops fetalis are outlined and briefly discussed. The article concludes with delivery recommendations and discusses a future plan of action for the diagnosis of hydrops fetalis.