Defines the functional requirements for the project including the different levels of business and end user requirements, and the functional areas of the business processes.

Functional requirements specify particular results of a system and may be calculations, technical details, data manipulation and processing and other specific functionality that define what a system is supposed to accomplish. This is contrasted with non-functional requirements which specify overall characteristics such as cost and reliability.

Behavioral requirements describing all the cases where the system uses the functional requirements are captured in use cases.

Functional requirements are supported by non-functional requirements (also known as quality requirements), which impose constraints on the design or implementation (such as performance requirements, security, or reliability). The plan for implementing functional requirements is detailed in the system design, while the plan for implementing non-functional requirements is detailed in the system architecture.

The Functional Requirements Document contains the following topics:

Purpose
      Project Description
      Project Approach
      Goals, Objectives and Scope
      Business Drivers
      Stakeholders
      Assumptions, Dependencies and Constraints
      Risks
      Costs
      Delivery Dates
Process Information
      Current Processes
      New Processes or Future Enhancements
Requirements Information
      Functional Requirements
      Infrastructure Requirements
      Other Requirements
      Non-Functional Requirements
Interfaces
      System Interfaces
      Software Interfaces
      Hardware Interfaces
      Software Interfaces
      Communications Interfaces.

Scroll down to the IT Functional Requirements Document example below.