The Ellis Act does not preempt San Francisco’s Rent Ordinance section 37.9A which requires landlords exercising their right to remove units from the rental market to give the displaced tenants a specific notice of their right to relocation payments and to make the required relocation payments. This decision also holds that strict, not substantial compliance, is required with the ordinance’s notice requirement. Here, the notice didn’t mention rights to relocation payments for children and so was ineffective, creating a defense to the landlord’s unlawful detainer action, even though the evicted tenants didn’t include children.