Acknowledging the works of others in nonfiction is a standard practice. But it’s the most neglected part in many cases. This chapter presents the need for properly crediting the contributions of others in nonfiction. A source is referenced for purposes such as presenting ideas and providing supporting or opposing information for arguments. When citing in nonfiction, all the elements of a reference should be included. A writer should be aware of the wrong practices in referencing such as dumping references, lazy writer syndrome and the use of dated works. Following an accepted style of referencing is required for consistency. Proper and complete referencing enhances the credibility of writers and the value of their books and avoids the issue of plagiarism. The chapter enlightens writers on best practices in referencing while cautioning against unprofessional trends often found in nonfiction.