An unlawful detainer action is a specific type of lawsuit which mainly addresses the issue of possession i.e. the right to occupy the apartment. The landlord files this type of action in order to recover possession of the apartment. The San Francisco Rent Ordinance only allows evictions in certain instances so long as the unit is a protected unit. Trials are set in these matters within a very short period of time so it is imperative that all protections are afforded. To begin the unlawful detainer process, a landlord must properly serve a Three Day Notice (3 Day Notice). The form of the 3 Day Notice must follow strict guidelines or else it can be challenged. Without a valid 3 Day Notice the entire unlawful detainer may be dismissed. Should an answer be filed without challenging the 3 Day Notice, certain defects may be waived. It is imperative that you consult an attorney who has knowledge of these proceedings in order to afford you of all of your options when responding to an unlawful detainer lawsuit.