How to Write an Annotated Bibliography

Woman using laptop in library

Academics use annotated bibliographies in a research paper or dissertation to validate the sources used by the researcher. Each entry includes bibliographic information, as well as a short paragraph indicating the value of the book/magazine/website.

Defining an Annotation

An annotation is a summary of the work and an evaluation of its relevance, currency, and value. The annotation should be approximately 150 words, in paragraph format. The main thesis of the book/article/video must be included, as well as how that thesis might relate or connect to the researcher's own work.

Step One: Gather Your Resources

Decide which resources to use based on the date of the book or article, the author's knowledge of the field, and the resource's relevance to your argument. Gather several valid resources on each facet of your subject so you can compare them. Start making notes as you consider the following.

  • Date: In most cases, the recent published findings are usually the most accurate, so contemporary writings will often best suit your purposes. However, in some subject areas (i.e. history and literature), the older the work, the better.
  • Author's knowledge: Check out the author's bio on the back cover of the book or do a quick Google search. Be sure that person is qualified in his/her field.
  • Relevance to argument: Consider whether the work will help you further explain a point you want to make or perhaps offer you some details that will help you flesh out your argument. Conversely, perhaps the work is on the other side of the argument. Use that information to your advantage.
  • Multiple perspectives: Decide whether the resources provide several perspectives on your research topic. The resources should support each other (i.e. dates and facts should agree), but they should also offer more than one point of view on your subject.

  • Strength: Consider how strong or weak each resource is and add that commentary to your annotation.

Step Two: Choose the Correct Citation Format

As in a bibliography, every source you use is listed in a distinctly different format, and that format is determined by the citation format appropriate for the subject matter. Be sure you are following the appropriate style for your purposes.

The different types of citation formats include:

  • MLA style (Modern Language Association) is utilized for resources that could be considered part of the Humanities curriculum: History, Rhetoric, Literature.
  • APA style (American Psychological Association) is the style used for citing sources that fall under the Behavioral and Social Sciences.
  • CMS style (Chicago Manual Style) is most often used by editors and can be adapted to almost any subject matter.

Other subject areas (particularly the sciences) are even more specific in the citation styles they utilize.

It's wise to use a guide or a citation tool like EasyBib, CitationMachine, or BibMe. Simply plug in all pertinent information, and the citation generator spits out your citation in correct format.

Step Three: Determine the Type of Annotations To Use

There are two types of annotations: summative and evaluative.


A summative annotation summarizes the work and details the author's main ideas and includes information on:

  • Main idea of the work
  • Author's major points
  • Conclusion

Here's one example of a summative annotation offered by Professor Dan Macnaughton:

"Achebe, Chinua. "An Image of Africa: Racism in Conrad's Heart of Darkness." Heart of Darkness. Ed. Robert Kimbrough. New York: Norton, 1988. 251-62. Print. An essay by Nigerian author Achebe on the prevalent image of Africa in the Western imagination, focusing on racist dimensions of Conrad's Heart of Darkness. Achebe presents an interpretation of the function of the images of Others in the construction of cultural identity and identifies a need on the part of 'the West' to denigrate and dehumanize Africa."


An evaluative annotation is a critical annotation that not only summarizes the author's work (as a summative annotation does), but also includes:

  • Information about the author's stance and tone
  • Importance of the work to the rest of the literature on the subject
  • Author's qualifications
  • Analysis of any omissions or contributions the work has made
  • Accuracy of the work and its relevance to the researcher's work

The same text presented by Professor Macnaughton (above) reads differently when written as an evaluative annotation, as you can see below:

Achebe, Chinua. "An Image of Africa: Racism in Conrad's Heart of Darkness." Heart of Darkness. Ed. Robert Kimbrough. New York: Norton, 1988. 251-62. Print. A provocative essay by the influential Nigerian author Achebe on the prevalent image of Africa in the Western imagination, focusing on racist dimensions of Conrad's Heart of Darkness. Achebe presents an interpretation of cultural identity and identifies a pervasive need on the part of 'the West' to denigrate and dehumanize Africa. This controversial essay has been tremendously influential in recent discussion of multicultural education but has received by no means universal assent.

Step Four: Follow Proper Annotated Bibliography Structure

Each annotated bibliography citation should follow the following guidelines:

  • 100-150 words long in paragraph format
  • Written in third person, academic voice
  • Whole sentences
  • Author information and evaluation
  • Purpose of the work
  • Summary (or evaluation) of the text
  • Reading level or difficulty
  • Comparison to other works in the field
  • Findings or conclusions

Step Five: Organize Your Annotated Bibliography

Now that you've created your entries, you probably have a long list of resources that need some organization. Depending on the assignment, you have several choices of how to organize annotated bibliographies. The person assigning the bibliography might have preferences, but the researcher may also choose to sort their bibliography for usefulness or ease of comparison.

  • Alphabetical: The most commonly used, an alphabetical annotated bib lists all the sources the way they would normally be listed in a bibliography. Here's an example in MLA format as written for a Freshman Comp report. An example of an APA style alphabetical annotated bib shows a few differences. Here's another example in CMA format.
  • Chronological: By listing the resources in chronological order, the researcher can often point out the relevance of the materials studied and the differences between the current ones vs. the original research done by specialists in the area. This type of annotated bibliography might be used in a scientific paper where recent studies might supplant studies previously done. This is an example of chronological format written for a paper on Lewis and Clarke.
  • Topical: Sorting annotations by topic enables the reader (and the researcher) to see whether any of the subjects discussed in the paper have received more attention than others. This type of bibliography is often used for very large projects, such as this example from Iowa State University's Library.
  • Publication format: Various publication formats include books, magazine articles, literary resources, documentaries, videos, audio sources, interviews, government documents, web pages, newspaper articles, and other publications. Splitting books from articles and videos from government documents may be helpful when determining how many different types of resources were utilized. The more varied the resources, the more wide-ranging the research.

Step Six: Edit

Edit your complete annotated bibliography so each entry is approximately 150 words, contains all the details noted in step four, and check to make sure that each citation is appropriately written.

Writing an Annotated Bibliography

Preparing an annotated bibliography helps the writer/researcher think critically about the resources used. If the researcher is at the level where s/he is considering how they might contribute to the field of knowledge already available about his/her subject, an annotated bib reveals the body of work already written and highlights where the researcher's work might fit. Writing an annotated bibliography helps the researcher establish an argument supporting the relevance of his/her own paper and can prove that his/her research has been extensive and valid.

Detailed Analysis for Future Scholars

Your annotated bibliography might be used by other scholars in the future, so don't be afraid to be analytical! Be succinct but unafraid to offer future readers information about which resources are solid and informative and which should be ignored.

Was this page useful?
Related & Popular
How to Write an Annotated Bibliography