This is where the parties agree on the method in which they will give notice to one another for when it is required in the lease. For example, renewal, termination, assignment, and subletting (among others) are all provisions that may require notice to be given to other parties. It is important when giving notice to ensure that these provisions are strictly followed so either party cannot bring a claim that notice was not sufficiently provided. For example, if notice of renewal requires notice by fax, and the tenant provides notice via email, then the landlord may try to claim that the lease had not been renewed (success of this tactic is not guaranteed - but it is a common tactic), if their desire is to replace the unit with a higher-paying or higher-quality tenant.