---
title: session
framework: arkit
role: symbol
role_heading: Instance Property
path: arkit/arsessionproviding/session
---

# session

A contract to declare an AR session.

## Declaration

```swift
var session: ARSession { get }
```

## Discussion

Discussion Some clients may use key-value observation (KVO) to be notified when this property changes values. To support KVO, Swift classes that adopt ARSessionProviding should mark its session as @objc and dynamic.