The three core aspects of SAFe

I get into quite lively discussions about "What is SAFe?". So, I want to boil down SAFe to three core aspects. When you have these things in place, you're set out in the right direction.

Team of Teams

At the root of SAFe is a team of teams. Like a developer is a vital component of a Scrum team, in the bigger picture, an agile team is a vital component of an agile organization.
The most important aspects of a Team of Team are the same as those of a single Scrum team:

• Uniting Vision
• Shared Goals
• Collaboration

The Team of Teams will be much more powerful than a group of individual teams. A Team gains power and effectiveness by contributing as a valuable member in this Team of Teams.

Systemic View

A Scrum team self-organizes to effectively meet the Sprint Objectives. In a large organization, the most pressing impediments are either at the touchpoints between teams - or even completely outside the team scope.
The following systems need to be considered:

• The Product 
• The Value Stream
• The Enterprise

A team is a component that both affects these systems - and is affected by these. Teams need to understand how changes to their way of working affects the system - and management needs to understand how modifying the system affects the teams.

Inspect and Adapt

Agility implies doing the right thing as we learn what this right thing is. Inspect and Adapt requires taking a systemic view to do properly - and a Team of Teams to be effective. The following items need to be inspected+adapted scrutinously:

• The Product
• The Process
• The Structure

The motor of agility is a functioning I+A mechanism. Ceremonies like System Demos (Reviews) and Retrospectives both at Team and System level are essential. A mindset of Experimentation and Feedback is necessary to be successful with I+A.

Summary

People who look at the "SAFe Big Picture" feel compelled to note that it's quite complex and has an overwhelming amount of prescriptive structure. Be at ease.
If you are concerned about the numerous roles, artifacts, the suggested practices or even the Big Picture itself - that's okay. They are not what you should focus on. They are provided as guidance to help you with the most common problems encountered when dealing with large product development.

Build a Team of Teams. Think in Systems. Inspect and Adapt.

Do these things and you will succeed.