There are 4 different levels of SAFe in 4.0 version onwards. They are shown in the figure below: Team Level-: This level is the same as that of what we know about Scrum, it’s Artifacts, roles and events/ceremonies. All scrum teams are part of one or the other ART (Agile Release train). ART is explained in the below diagram. Basically, this is a team of 50-100 people (cross-functional) responsible for defining and deploying the new system, plan, commit and delivers the solution to the customer in a particular time frame. Program Level: At this level product and program manager has the authority to define the Backlog. At this level, different roles are DevOps, System Architect, RTE, Product Management, System Team, Business owners, Customer, UX Architect. The main events of this level are: ART: This level value of SAFe is delivered by ART. Iteration is for the Team and train is for the program. It delivers a value stream to the organization. SAFe artifact hierarchy is Epics->features->user stories. User Stories then drill down to the team level. Various team (from marketing, development, quality, operations, and deployment) forms 'Release Management Team'. They will approve routine releases of quality solutions to customers PI planning-  Duration is about 8-12 weeks. A very huge event where all the cross-functional team members across the globe participate and work towards the common goal. A valuable increment of the system is developed and delivered. PI deliverables: System Demos-At the end of each PI (Every 2 weeks) the full integrated work of all teams is demoed. This is in addition to each team iteration demo. Stakeholders provide the feedback and corrective action needs to be taken if required. Inspect and Adapt- This is also held at the end of each PI to demonstrate the solution, get the feedback, solve the problem and identify improvement areas Architectural Runway- It is an existing code base, components, technical infrastructure on top where new features are developed without much change in code. Release Any Time- This separates the development cadence from the solution release cycle. Trains may release whatever is needed at any time. Value Stream Level-This level is optional but required in below cases. The organization is big in size Complex solutions The solution requires multiple ART’s System challenges Portfolio Level- Highest level of concern/involvement in SAFe is portfolio Level. It provides basic budgeting and other governance mechanisms. This way it assures that investment in the value streams provides the basic returns for the enterprise. Portfolio Program Management are key stakeholders and they are responsible for delivering the business results. Here the backlog contains the EPICS (Which contains many features.), EPIC owners are responsible for driving this. The main roles involved are Enterprise Architect, PPM (Program Portfolio Management), Epic owners. Events are Strategic business planning and Epic planning. This is frequently asked in SAFe Agile interview questions.