The Planning and Compulsory Purchase Act 2004 made substantial changes to the English Development Plan system. It did away with both Structure Plans and Local Plans, in favour of Local Development Frameworks (LDFs), which are made up a number of Local Development Documents (LDDs) and Supplementary Planning Documents (SPDs). The Regional Spatial Strategy (RSS), which is produced by Regional Assemblies in England, replaces the Structure Plan as the strategic planning document (i.e., the RSS that's targets for housing and employment development within each district in a Region in the future). A variation on this approach exists in Wales.