Interstitial cells of Cajal (ICC) aroused much interest among neuroanatomists at the beginning of the century. These small cells are organized into networks, found in a variety of smooth muscle tissues and are now considered by many authors to be responsible for the pacemaker activity of the gut and may have novel physiological functions. This review discusses the presence of ICCs outside the gastrointestinal tract in different systems of the body especially in urinary tract, female genital system and placenta, and the new possible roles in these organs. It is important now to discover the conditions that are responsible for ICCs loss and develop new therapies to relieve patients of this problem.