Features and capabilities are essential to the SAFE Requirements Model. They are absolutely necessary in the defining, planning, and implementing Solution value.

A Feature is an ability that fulfills a stakeholder requirement. Every feature has two core concept -  a benefit hypothesis and acceptance criteria, and is sized or split as necessary and made ready to be delivered by a single Agile Release Train (ART) in a Program INCREMENT (PI). Acceptance criteria in features are used to determine whether the implementation is correct and delivers the BUSINESS benefits. Features can include additions or changes to existing functionality. A feature SPANS over a single ART (Agile Release Train) and broken down into stories targeting the completion in a PI. Product Managers, in collaboration with Product Owners, and other key stakeholders, define features in the local context of an ART. Some arise as a result of splitting epics.

A Capability is a higher-level solution behavior that typically extents multiple ARTs (Agile Release Train). Capabilities are sized and broken down into multiple features to aid their implementation in a single PI. They exhibit the same characteristics and practices as features e.g. they are described using a phrase and benefit hypothesis and are sized to fit within a PI, however, they often take multiple ARTs to IMPLEMENT.