The Livestock Conservancy, formerly known as the American Livestock Breeds Conservancy (ALBC) and prior to that, the American Minor Breeds Conservancy, is a nonprofit organization focused on preserving and promoting rare breeds, also known as "heritage breeds" of livestock. Founded in 1977, through the efforts of livestock breed enthusiasts concerned about the disappearance of many of the US's heritage livestock breeds, The Livestock Conservancy was the pioneer livestock preservation organization in the United States, and remains a leading organization in that field. It has initiated programs that have saved multiple breeds from extinction, and works closely with similar organizations in other countries, including Rare Breeds Canada. With 3,000 members, a staff of eleven and a 19-member board of directors, the organization has an operating budget of over a million dollars.

In modern agriculture, a rare breed is a breed of poultry or livestock that has a very small breeding population, usually from a few hundred to a few thousand. Because of their small numbers, rare breeds may have a threatened conservation status, and they may be protected under regional laws. Many countries have organizations devoted to the protection and promotion of rare breeds, for which they each have their own definition. In botany and horticulture, the parallel to rare animal breeds are heirloom plants, which are rare cultivars.