Greater Washington Research Program (Brookings)
The Program seeks to "improve public policy in the region by identifying policy issues, presenting data and analysis of policy options, and convening leaders for focused dialogue." Many reports by the Program are available in full text.
D.C. Historic Preservation Law Project
Georgetown Law Library project providing full-text access to the D.C. Mayor's Agent for Historic Preservation Decisions and a guide to D.C. historic preservation law.
DC Watch is an online magazine covering DC politics and policies; includes a useful bibliography (last updated 2012)