Private sector renting is largely governed by many of the Landlord and Tenant Acts, in particular the Landlord and Tenant Act 1985 which sets bare minimum standards in tenants' rights against their landlords. Another key statute is the Housing Act 2004. Rents can be freely increased at the end of a usual six-month duration, on proper notice given to the tenant. A Possession Order under the most common type, the Assured Shorthold Tenancy (AST) is usually obtainable after eight weeks/two months of unpaid rent, and at the court's discretion after serving the tenant with a Section 8 notice (under the Housing Act 1988 as amended) for a lesser period for all assured tenancies — and on other grounds which defer to the landlord's ownership of the property. If the tenancy is an AST then any possession order will not take effect until six months has passed into the initial tenancy. A tenancy of someone who has been in occupation since before 15 January 1989 usually, if not a shorthold from the outset following their inception from 1980 onwards, may be a "regulated tenancy" with many more rights, especially under the Rent Act 1977 and Protection from Eviction Act 1977, introduced by the Third Wilson ministry.