 The modern interpretation of the tenant-landlord relationship has hinged on the view that leases include many elements of contract law in addition to a simple conveyancing.In American landlord-tenant law, many of these rights and duties have been codified in the Uniform Residential Landlord and Tenant Act.Landlord–tenant law generally recognizes differences between residential and commercial leases on the assumption that residential leases present much more of a risk of unequal bargaining power than commercial leases.