A business that leases real estate and improvements (buildings, etc.) in the form of space for offices, a warehouse, a restaurant, a nail or hair salon, a clothing store, a coffee shop, or other commercial (nonresidential) space will usually be required to sign a written contract known as a commercial lease agreement.

The tenant (the business occupying the space) who signs a commercial lease agreement is generally expected to be a more savvy, sophisticated, and informed tenant (also known as a lessee) than a tenant in a residential lease, and the law usually does not provide a commercial tenant with the same protections as residential tenant receives.

Because the law does not provide a commercial tenant with many protections, it is up to the commercial tenant to read, understand, and negotiate protections in a proposed lease agreement before signing it, as most every paragraph in a commercial lease agreement can have a significant impact on a business’s operations and financial stability.

A commercial landlord’s responsibilities are generally determined by the specific language in the written lease agreement and the state's contract law.

Contract law in most states recognizes an implied duty of good faith and fair dealing between parties to a contract, and a landlord who does not perform its responsibilities under a commercial lease in good faith or who is not fair in its dealings with the tenant may be in breach of the landlord’s implied duty of good faith and fair dealing.

In California, businesses that lease commercial spaces such as offices, warehouses, or retail stores enter into commercial lease agreements. Unlike residential tenants, commercial tenants are considered more knowledgeable and are expected to understand and negotiate the terms of their leases. California law does not provide the same level of protection to commercial tenants as it does to residential tenants. Therefore, it is crucial for a business to thoroughly review and negotiate the lease terms to ensure they align with their operational and financial needs. The responsibilities of a commercial landlord in California are primarily outlined in the lease agreement itself, supplemented by the state's contract law. While specific protections may not be statutorily provided, California contract law does recognize an implied covenant of good faith and fair dealing. This means that a landlord must act in good faith and deal fairly with the tenant, and failure to do so could constitute a breach of this implied duty. It is advisable for businesses to consult with an attorney to understand their rights and obligations under a commercial lease agreement and to ensure that the lease terms are fair and equitable.