Chicago Style is often used in many different fields. There are two basic forms of citation: the humanities generally use a notes and bibliography format, while physical, natural and social sciences generally use the author-date filing system.
Autor-Date Filing System:
In-Text citations should be done similar to MLA:
1) Book: (Smith 2003).
2) A specific quote, idea or summary from a book: (Smith 2003, 45) or page range (Smith 2003, 45-46).
3) Book with Two Authors: (Smith and Wesson 2003).
4) Book with More than Three Authors: (Smith et al. 2003).
5) A Chapter in a Book: (Smith 2003, 65-83)
6) An Organization as Author: (United States Department of Agriculture, 2009).
7) A Journal Article: (Smith and Wesson 2003, 1089-1134).
8) A Magazine Article: (Smith 2003, 78)
Notes/Bibliography Filing System:
In the in-text citations, include a tiny footnote number—for example, “Fourscore and seven years ago”1 and at the bottom of the page, include the corresponding footnote for that quote, paraphrase, summary, etc. The footnotes should be formatted as follows:
1) Book: John Henry Smith, Why I Never Write in Chicago Style Format (New York: Long Island Publishers, 2011), 89.
2) Book with Two Authors: John Henry Smith and George Wesson, How to Win Friends and Influence Spartans (Boston: Little, Brown Publishers, 1997), 162-177.
3) Book with Four or More Authors: Emily Smith et al., Politics and Privilege (New York: Centennial Press, 2005), 301.
4) A Chapter in a Book/Compilation: Joseph G. Judson, “Why I Could Never Stay Out Of Trouble,” in Diary of an Old Fool (California: PlayTime Publishers, 2003), 897.
5) A Journal Article: J. Abram Hooks & Linda Windwater, “Correlation Between Attachment and Early Childhood Reading Level,” Journal of Psychology 16, no. 3 (2010): 450-456.
6) An Online Journal Article: J. Abram Hooks & Linda Windwater, “Correlation Between Attachment and Early Childhood Reading Level,” Journal of Psychology 16, no. 3 (April 2010): 450-456, accessed June 4, 2012. http://doi: http://dx.doi.org/10.1016/j.ijintrel.2
7) A Website: Bob Johnson, “5 Tips for Fantastic Fan Installation,” Hobby Helper Online, accessed February 1, 2014. http://www.hobbyhelper.com/
8) A Magazine Article: Katherine Burse, “Weight Loss Pills Myths,” Fashion Magazine, August 2013, 56.
For more examples, visit the New York Libraries’ page on the Chicago Manual of Style.