Routine and microscopic examination of stool is an important test in clinical pathology. In this chapter, importance of the examination of stool, procedure of stool sample collection for routine and microscopic examination are described. Special tests like occult blood test, its indications and procedures, reducing substances in stool are also narrated. Definition of diarrhea, dysentery, their presentation, etiological factors and stool findings are presented in tabulated form. Steatorrhoea, its definition, etiology and diagnostic features in stool are also discussed.