• Business requirements — enterprise/organisational needs, goals and objectives
• Stakeholder requirements — those elements that act as connectors between business requirements and other classes of solution requirements and the way in which a given stakeholder will interact with the solution or end product
• Solution requirements — attributes or characteristics of a solution that achieve the business and stakeholder requirements, including:
> Functional requirements — behaviour and/or information that the solution will manage
> Non-functional requirements* — circumstances or environment in which the solution or end product must be able to operate
• Transition requirements — temporary capabilities to transition from current to future state, typically through solution assessment and validation