Market Research Society: http://www.mrs.org.uk/
The home page of the organisation representing UK market research companies contains some useful insights into the challenges of collecting information about a changing business environment.

Association for Qualitative Research: www.aqr.org.uk
The Association for Qualitative Research is a non-profit organisation. The website contains some case studies.

The World Association of Opinion and Marketing Research Professionals: http://www.esomar.org/
ESOMAR's mission is to promote the use of Opinion and Marketing Research, for improving decision making in business and society, worldwide.

Office for National Statistics: http://www.statistics.gov.uk/
A portal for the UK government's statistical service, which includes freely available data and a listing of data sets which can be purchased.

Eurostat: http://europa.eu.int/comm/eurostat
Home page of the EU's statistics office.

SecondaryData.com: www.SecondaryData.com
A web site provided by Decision Analyst, Inc. which offers organized, indexed and annotated links to sources of free economic and marketing research data available on the Web. Includes links to demographics, Internet usage, government figures, international data, and public opinions. There's also a large general reference section of links, and links to tutorials on how to conduct research. Most of the links go to free data.

World Population: http://www.census.gov/ipc/www/idb
World population data from the US census.

Organization for Economic Co-operation and Development: http://www.oecd.org
This site provides a summary of member states' economic and demographic statistics.

The Institute for Fiscal Studies: http://www.ifs.org.uk
IFS is an independent research organisation, which aims to provide high quality economic analysis of public policy. The IFS home page provides links to IFS surveys and other online economics and social sciences resources.

Business Cycle Indicators: http://www.tcb-indicators.org
The Conference Board is a not-for-profit, non-advocacy business research and membership organization with 2,800 companies and other enterprises in 63 counties. It provides timely research on economic trends and is a frequently quoted private source of business information.

Confederation of British Industry: http://www.cbi.org.uk/home.html
The CBI represents companies from all sectors of UK business and is the premier organisation speaking for companies in the UK. Its web site provides details of CBI surveys and discussion of topical economic issues.

UK Treasury: http://www.hm-treasury.gov.uk
Home page of HM Treasury, which includes analysis of recent government economic measures, revenue and expenditure analysis. Data from this source is used as a basis for forecasting future levels of household disposable income.