When it comes to implementing or constructing large and complex systems (such as an enterprise software system), the work requirements and conditions should be properly documented. Statement of Work (SOW) is such document that describes what needs to be done in the agreed contract.

Usually, the SOW is written in a precise and definitive language that is relevant to the field of business. This prevents any misinterpretations of terms and requirements.

An SOW covers the work requirements for a specific project and addresses the performance and design requirements at the same time.

Whenever requirements are detailed or contained within a supplementary document, SOW makes reference to the specific document.

The SOW defines the scope and the working agreements between two parties, typically between a client and a service provider. Therefore, SOW carries a legal gravity as well.
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