The usefulness of bowel preparation before small bowel capsule endoscopy is surrounded with controversy. In this concise review, the available literature is discussed. Current evidence indicates that bowel preparation with purgative agents increases the diagnostic yield of the procedure by improving small bowel mucosal visualization compared with a clear liquid diet or overnight fast. With respect to the type of purgative, most evidence supports the use of polyethylene glycol (PEG). The optimal dose of PEG that needs to be administered before capsule endoscopy is not entirely clear, but 2 l appears to be sufficient.