The Defence of Britain Project (1995-02) has recorded nearly 20,000 20th century military sites in the United Kingdom, including pillboxes. As well as recording the 20th century militarised landscape of the United Kingdom, the project also informs heritage agencies at local and national level with a view to the future preservation of surviving structures. Full details of the project are at:
English Heritage has undertaken a series of research projects to improve our understanding of second world war defences in the context of the many other sites that represent our defence heritage. Options for preservation include statutory designation, although it would not be appropriate to designate all of the many thousands of surviving pillboxes—careful selection is necessary. Alternatively, many of these structures have local significance and their recording on local authority Historic Environment Records is another way of improving understanding and protection.