1. Duty to deliver possession of the leased property
   Under the traditional rule, a landlord was not obligated to provide possession of the property to the tenant at the inception of the leasehold. However, most states in America have adopted statutes that require a landlord to provide possession to the tenant when the lease begins.
2. Duty to repair
   Under the common law rules, a landlord is not obligated to perform repairs of the leased property. However, modernly, most leases contain covenants that obligate the landlord to perform repairs of the property.
3. Quiet Enjoyment
   Every lease has an implied covenant of quiet enjoyment. In the case of actual or constructive eviction, the covenant of quiet enjoyment is breached and the tenant is free from his/her obligations to pay rent.
4. Duty to keep common areas safe
   Landlord generally has a duty to keep the common areas (e.g. swiming pool in an apartment complex) safe.

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