The Local Housing Allowance (LHA) scheme was introduced in 2008 - it is the scheme used for assessing how much Housing Benefit a claimant living in privately rented (ie not social housing) accommodation is entitled to - unless excluded from it.

Note that the proposed Social Housing LHA Cap - which had been due to arrive in 2019 - has been cancelled.

NOTE: Not a benefit issue but worth knowing about
From 1st June 2019, for private tenancies, the Tenant Fees Act 2019 came into force. Private Landlords are not able to charge admin fees for references, credit or immigration status checks, contract renewal or leaving at the end of a contract (thought they can make a "reasonable" charge for ending a tenancy early, late rents, and other costs). There is a cap of one week's rent for a holding deposit; 6 weeks' rent for security deposits. Failure to comply can incur fines of up to £5000 (first offence) or up to £30,000 (subsequent offences.) Tenant Fees Act guidance here.