Tenancy at will is a type of rental agreement where a tenant occupies a property with the landlord's permission but without a fixed lease term. This arrangement can be terminated by either party at any time, usually with a short notice period. It offers flexibility for both landlords and tenants, as it does not bind them to a long-term commitment. In a tenancy at will, the tenant pays rent, but the terms can be informal and may not require a written contract. This type of tenancy is often used in situations where the landlord and tenant have a good relationship or when the rental period is uncertain.