The Chicago Manual of Style includes two slightly different documentation systems: (1) notes and bibliography (NB) and (2) author-date. The notes and bibliography style is preferred by many in literature, history, and the arts.
In the NB system, you mark within your paper where you have cited something by adding a number, which refers to a detailed reference either at the bottom of the page (footnote) or at the end of the paper (endnote). These notes indicate the specific place in your source you are referencing.
The bibliography includes complete information for each item, with the items arranged in alphabetical order by author's last name.
Purdue's Writing Lab provides an example of a paper formatted using Chicago NB style.
The 18th edition of The Chicago Manual of Style was published in fall 2024. As of March 2025, Zotero has not released a citation style for the 18th edition. The differences between the 17th and 18th editions are significant enough that using the 17th CMOS citation style will not create citations that conform to the 18th edition's rules. If you want to use Zotero, plan to use the 17th edition style. Check back here for updates.
Evidence Explained by Citation managers (also called reference managers or bibliographic management software) offer a way to save, organize and manage references.
All citation management programs let you:
Four popular citation managers are listed below. The Manage Your Citations guide provides more information about the differences between them.