Manure has long been recognized as a valuable source of nutrients. The product is dynamic, and an understanding of both chemical and biological mechanisms is required to optimize its use. This chapter provides a comprehensive overview of manure. Here, the basics of manure composition, collection, storage, and application are summarized with an emphasis on both scientific and practical considerations. Long-standing challenges in manure management, the history of responses, and modern approaches are reviewed. This chapter presents many ideas for future research and problem-solving.