A South Dakota single-member LLC operating agreement is an internal document used by the sole owner of a limited liability company to outline their rights, responsibilities, and liabilities in relation to the company. In addition to protecting personal assets from company obligations, the operating agreement also allows the owner to determine the company’s policies, procedures, and other internal structures. While the state of South Dakota does not require an LLC to implement this document, the business would be subject to general state rules governing LLC operations without an operating agreement in place. The document also provides additional tax benefits for the company. The owner is advised to sign the document in the presence of a notary public.