British Security Industry Association - The British Security Industry Association is the trade association for the professional security industry in the UK.
https://www.bsia.co.uk/
Industrial Security Doors Ltd - Industrial Security Doors is a London based fitter and supplier of security doors and other folding and roller shutters.
http://www.isd.me.uk/
Security Industry Authority (SIA) - The Security Industry Authority (SIA) is the organisation responsible for regulating the private security industry in the UK.
https://www.gov.uk/government/organisations/security-industry-authority
