An ostomy pouching system is a prosthetic medical device that provides a means for the collection of waste from a surgically diverted biological system (colon, ileum, bladder) and the creation of a stoma. Pouching systems are most commonly associated with colostomies, ileostomies, and urostomies.

Pouching systems usually consist of a collection pouch, a barrier on the skin, and connect with the stoma itself, which is the part of the body that has been diverted to the skin. The system may be a one-piece system consisting only of a bag or, in some instances involve a device placed on the skin with a collection pouch that is attached mechanically or with an adhesive in an airtight seal, known as a two-piece system.

The system used varies between individuals and is often based on the medical reason, personal preference and lifestyle.