Skip to Main Content

Grey Literature

Start your grey literature search with this guide containing resources and strategies for discovering research produced outside traditional commercial or academic publishing channels.

How to Search for Grey Literature

Grey literature, characterized by its rapid production and diverse array of originating entities, offers a valuable resource for accessing contemporary and contextually relevant information. However, the decentralized nature of its dissemination poses challenges to its discovery compared to conventional scholarly works. Unlike scholarly journals and books, which benefit from professionals' systematic cataloging, organization, and preservation efforts, grey literature typically lacks standardized cataloging procedures. Consequently, its accessibility to researchers is hindered by inadequate or inconsistent cataloging practices among producing organizations. This deficiency in cataloging infrastructure is further exacerbated in the realm of digital documentation or materials from defunct organizations, where preservation mechanisms are often absent.

Moreover, grey literature's departure from traditional metadata standards compounds the difficulty in locating cited documents, even when citations are accurate. Compounding these challenges, the absence of a centralized repository for grey literature necessitates researchers to navigate disparate repositories maintained by individual organizations to access pertinent materials. Thus, while grey literature offers a wealth of timely information, its decentralized nature and lack of standardized cataloging mechanisms render it more elusive than its scholarly counterparts.

Tips for Searching for Grey Literature

During academic inquiry, researchers frequently encounter scholarly works incorporating references to or citations from grey literature. This practice expands the breadth of available literature on a given subject and facilitates the identification of entities responsible for disseminating such materials. Notably, engaging in citation chasing of this nature underscores the perceived authority of the respective grey literature-producing organizations within the subject domain, as evidenced by their incorporation into scholarly discourse. Furthermore, citation tracing aids in discovering pertinent resources, given the close thematic alignment between cited sources and the focal content of the referencing article.

For instance, the article titled "Global Climate Implications for Homelessness: A Scoping Review," published in the Journal of Urban Health, references various sources, including two studies or reports attributed to the United Nations, illustrate the integration of both scholarly and grey literature. While the primary focus remains on scholarly discourse, such citations enrich the scholarly dialogue by incorporating insights from grey literature sources. Additionally, noting the originating organizations during research endeavors enhances the researcher's awareness and potential utilization of such sources in future research.

The Google Advanced Search differs significantly from the simple default Google Engine Search. There are many different search fields available in this Advanced Search, with one of the most convenient areas for grey literature being the site or domain field. If there is a singular site you are looking to complete a search on, it can be done here. Similarly, if you want to only look for information on U.S. government websites, it is possible to complete a search of only ".gov" websites. Type one of the following into the search bar:

  • Site:gov search words​ or phrases
  • search words​ or phrases
  • search words or phrases

Again, Google Advanced Search has many different search fields available in this Advanced Search. Another important area to point out for researching Grey Literature is the file type. You can limit search results to only one file format, such as .pdf or .xls, by choosing a specifier on the Advanced Search page. When searching for a specific kind of resource, this can be extremely helpful. It is also nifty when you just want to parse down your search a little more! Type one of the following into the search bar:

  • Filetype:pdf​

  • Filetype:ppt​

  • Filetype:svg​

  • Filetype:xls OR xlsx

Directories are lists of individuals or organizations, typically grouped or organized thematically. Directories are beneficial in identifying different organizations that may produce grey literature in the field of research you are interested in. Each directory depends on its coverage, so pick the appropriate directory for your topic. Remember that many directories can become outdated quickly, so check for updated or new web addresses or changes in the organization's name, missions, programs, or goals.  


The Open Think Tank Directory is an excellent example of a general searchable directory. As you can see below, it is also searchable by region, which can help in many areas of Global Studies research.

Tools for Searching for Grey Literature