Finding Grey Literature

Conference Proceedings Citation Index (Science and Technology)
This is an index to the published literature of the most significant conferences, symposia, seminars, colloquia, workshops, and conventions in a wide range of disciplines.

Check your institution

Dissertations and Theses (WorldCat)
All dissertations, theses, and published material based on theses cataloged by OCLC members.

Check your institution

Google Scholar
Provides a search of scholarly literature across many disciplines and sources, including theses, books, abstracts, and articles.

https://scholar.google.co.uk/

HMIC (Health Management Information Consortium)
Coverage includes official publications, journal articles, and grey literature on health service policy, management, and administration.  You need to use Open Athens to access this resource.

https://library.nhs.uk/knowledgehub/

OpenGrey (System for Information on Grey Literature in Europe)Open Grey – now decommissioned, but still available.  Coverage is best for the period 1980-2005. The Archive for OpenGrey material can also be found on the Dutch national centre of expertise and repository for research data. 

Official-documents.gov.uk
Official Documents is the official reference facility for Command and departmentally sponsored House of Commons Papers. All Command Papers and House of Commons Papers published from May 2005 onwards, as well as key Departmental papers, are available for free on the site in PDF format.

http://www.official-documents.gov.uk/

PsycExtra
A database of gray literature produced by the American Psychological Association (APA) in the field of psychology and behavioural science. Documents indexed in PsycEXTRA include newsletters, magazines, newspapers, technical and annual reports, government reports, consumer brochures, and more.

Check your institution

SCOPUS
Scopus contains conference proceedings.

https://www.scopus.com/search/form.uri?display=basic#basic