The Illinois General Assembly has recently amended the Landlord and Tenant Act to add a new requirement for landlords: when a unit changes over to a new tenant the locks must be changed or rekeyed. This applies to dwelling units only. The Act is not applicable for dwelling units in a building of 4 units or less when the owner occupies one of the units. Failure to comply will make the landlord strictly liable for all resulting damages from theft suffered by the tenant. See the Act for specifics.