The functional requirements document (frd) is a formal statement of a product's functional requirements. The frd is produced by business analysts or sometimes the technical team in response to the business. A functional specification document (fsd), also known as a functional requirements document (frd), is considered by many project management and software. [provide a list of contractual or task level assumptions and/or constraints that are preconditions to preparation of the frd. Streamline your project planning with our comprehensive functional requirements document template.