A Use Case describes what a piece of software does or needs to do. As a business user of IT solutions, a Use Case enables you to talk to technologists about your IT business needs in a manner they can understand. As a technical professional, a Use Case enables you to talk about technology to the business community without using technical jargon.

Use Cases are a commonly used business analysis technique to define the interactions between people and technology. They are the de facto standard for documenting and communicating functional requirements. Applying the lean philosophy of waste reduction to the Use Case concept creates a powerful tool for communication to and within an Lean or Agile Software Development team.

Writing a Lean Use Case is a skill that anyone in an organization can easily acquire. Learning how to write and manage lean business- and solution-level use cases is a major step in getting your IT applications to do what you want them to do. Knowing why you need a Lean Use Case, when to create one (especially in a lean environment), and where to put what information is critical to creating high-quality functional requirements.