Artifact: Vision
This artifact defines the stakeholders view of the product to be developed, specified in terms of the stakeholders key needs and features. It contains an outline of the envisioned core requirements, so it provides a contractual basis for the more detailed technical requirements.
Domains: Requirements
Work Product Kinds: Specification

This artifact provides a high-level, sometimes contractual, basis for the more detailed technical requirements that are visible to the stakeholders. It captures the "essence" of the envisaged solution in the form of high-level requirements and design constraints that give the reader an overview of the system to be developed from a behavioral requirements perspective. It provides input to the project-approval process and is, therefore, closely related to the Artifact: Business Case. It communicates the fundamental "why and what" for the project and is a gauge against which all future decisions should be validated.

Another name used for this artifact is the Product Requirement Document. 

Main DescriptionThe Vision document provides a complete vision for the software system under development and supports the contract between the funding authority and the development organization.  Every project needs a source for capturing the expectations among stakeholders.
Brief Outline

The vision document is written from the customers' perspective, focusing on the essential features of the system and acceptable levels of quality. The Vision should include a description of what features will be included as well as those considered but not included.  It should also specify operational capacities (volumes, response times, accuracies), user profiles (who will be using the system), and inter-operational interfaces with entities outside the system boundary, where applicable.

Representation Options

Tailor this artifact as necessary for your project's needs.  It is generally good practice to keep this artifact brief in order to be able to release it to stakeholders as soon as possible, and to make it easy for stakeholders to review and absorb. This is done by including only the most important stakeholder requests and features, and avoiding detailed requirements. Details may be captured in the other requirements artifacts, or in appendices.

It is important to express this artifact in terms of its Use Cases and primary scenarios as these are developed, so that you can see how this artifact is realized by the use cases.

Decide whether feature attributes (Requirements Attributes) are documented in the Vision or in the Requirements Management Plan. Decide what information is to be included in the Vision, and what is to be managed using requirements management tools such as Rational RequisitePro (see  Tool Mentor: Developing a Vision Using Rational RequisitePro ).

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