For Managed Security Services – MSSP. The Statement of Work or SOW clearly documents the items included in its particular service offering, deliverable or implementation, including SLAs, minimum requirements and exclusions. Used in conjunction with a Master Services Agreement or MSA for a first-time client engagement, additional SOWs are used to sell new; or modify existing services during the lifetime of a client relationship. For example, for the first service sold to a client, they will countersign the MSA and a SOW for that service. For additional services sold, or adds or modifications to the original SOW, the client will simply countersign additional SOWs. Using a one-time MSA along with SOWs shortens the total amount of additional paperwork needed to continue delivering new projects and services to a client during the lifetime of the relationship. This document is editable and can quickly be completed by tabbing through the required fields to complete them.