Business and Stakeholder Requirements define the business need in business terminology that all involved parties can understand, but the devil lies in the detail. Solution Providers (i.e., those responsible for building, buying, assembling, or configuring an IT application) need to know what the application must do, what data it will deal with, and what qualities it must possess to meet the business needs. In other words, they need Functional and Non-functional (aka Solution) Requirements at a level of detail that most subject matter experts can only provide when prompted and led.