Treatises are the most useful type of secondary sources and are book-length expositions on the law as it pertains to a particular subject. Treatises may be scholarly in nature, or geared toward a legal practitioner, such as a manual or handbook. Some treatises are designed to serve as practitioners’ tools. These works tend to address realistic legal problems and often provide useful features for practicing lawyers, such as forms and tables. Check the Library Catalog and "Treatises by Topic" for additional titles.A legal treatise may be a short, single volume or a large, multi-volume set. Many are available electronically as well as in print. Different kinds of treatises have different purposes.