While mentioned in guidance, there is no statutory requirement for local authorities to fund an SMR (although this was a provision in the England and Wales Heritage Protection Bill[2][3]) and there is great variety in implementation across the UK.
Some SMRs are simple card indexes, others are command line Unix databases and others are more modern and GIS-based.
Efforts to place SMRs on-line have met with success in certain parts of Britain, although some archaeologists have voiced concern that making vulnerable sites better known to the public endangers them further, especially through illicit metal-detecting.
In 2007, an updated version of best practice guidance for HERs "Informing the Future of the Past: Guidelines for Historic Environment Records"[4] has been made available on-line.
[5] In Scotland, the PASTMAP website[6] presents comprehensive national datasets on monuments, buildings, gardens and designed landscapes, wrecks, and an increasing number of local records.