What is meant by “grey literature” and how to search for it effectively

Grey literature is unpublished or semi-published information, materials or research that has not been produced by commercial publishers. This can include:

• Conference proceedings
• Dissertations and theses
• Government white papers or documents
• Preprints (full draft research papers shared publicly before they have been peer reviewed)
• Reports
  • Annual
  • Business and industry
  • Project
  • Research
  • Technical
• Working papers

The types of organisation responsible for producing grey literature include:

• academic centres and departments
• civil society or non-governmental organizations
• government departments and agencies
• private companies and consultants

Since grey literature is unpublished it can be hard to track down, and the fact that no one has previously peer-reviewed it means that there is no quick way of assessing its quality. Therefore, you should always evaluate it first before deciding whether it is good enough to use for your assignment. (For more advice on how to do this see the separate section on Evaluating Sources.)

Here are some search engines you can use to track down grey literature:

• BASE (Bielefeld Academic Search Engine)​
• The King's Fund Library 
• OpenAIRE
• OpenDOAR