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If a piece of land is in acompulsory registration area (now the whole of England and Wales), and is unregistered (see unregistered land), then the proprietor has an obligation to register the land when certain events occur. The number of such events has increased over the years, but it now includes:

1. Purchase of a Freehold estate for value, or assignment by gift, or transfer by the personal representative of a deceased owner, or by court order
2. As above for Leases of more than seven years
3. The grant of a Lease of any length that takes effect more than three months after grant
4. The creation of a first Legal mortgage over the land

It has always been possible to register voluntarily, and since the land registration act (2002) gives increased protection against adverse possession to registered land, there is now at least one incentive to do so.