The SOW details what the developer must do in the performance of the contract. Documentation developed under the contract, for example, is specified in the SOW. Security assurance requirements, which detail many aspects of the processes the developer follows and what evidence must be provided to assure the organization that the processes have been conducted correctly and completely, may also be specified in the SOW.
NISTIR 7622 under Statement of Work
(NIST SP 800-64 Rev. 2)