In an enormously important development for researchers worldwide, the World Bank has launched an Open Data Initiative under which it has opened up its databases for free public access.
For an extraordinarily rich array of data and research, go to http://data.worldbank.org/ . From this front page you can access country profiles for over 200 countries, view data for over 300 indicators.
At http://data.worldbank.org/data-catalog you can access the data catalogue, a listing of available World Bank data sources. This listing will continue to be updated as additional data resources are added. These resources include databases, pre-formatted tables and reports. Each of the listings includes a description of the data source and a direct link to that source. Where possible, the databases are linked directly to a selection screen to allow users to select the countries, indicators, and years they would like to search. Those search results can be exported in different formats. Users can also choose to download the entire database directly from the catalogue.
At http://data.worldbank.org/topic you can access data organised in accordance with sixteen topics – environment, financial sector, health etc.
At http://www.worldbank.org/reference/ you can access formal World Bank publications through the Online Bookstore, download over 65,000 free documents including operational documents (project documents, analytical and advisory work, and evaluations), formal and informal research papers, and most Bank publications, and access the Archives.