This page describes how to use the Dialogue System in a VR environment.

Oculus Rift Example Scene

You can download an Oculus Rift example scene from the Dialogue System Extras page:

To run the example scene in Unity:

Use Unity 5.1.2+.
Follow the instructions on the Unity 5.1 VR Getting Started thread (http://forum.unity3d.com/threads/unity-5-1-vr-getting-started.332316/). This includes downloading and installing the Oculus Runtime for Windows.
Download Oculus Utilities for Unity 5 from http://developer.oculus.com/downloads/.

Then play the example scene. The UI is spread across two world space canvases:

The dialogue panel is in actual world space next to Private Hart.
The alert panel is a child of the OVRPlayerController's CenterEyeAnchor so it always appears in front of the player.

The scene uses BasicLookInputModule. To select a dialogue option, look at it. Then click the mouse button ("Fire1") to select it.

Oculus Rift - Dialogue System Setup

In your own scenes, note the following:

Use Unity UI, not legacy Unity GUI.
To use look input as in the example scene, add the BasicLookInputModule script to your EventSystem.
Decide how you want your UI to appear in VR. The example scene presents two options: alerts are shown in the center of the player's vision regardless of where the player looks, and conversations occur on a panel in fixed world space.
You can use a different world space dialogue panel for each NPC by adding an Override Dialogue UI component to it.
You will usually want to set the Dialogue Manager's Default Sequence to Delay({{end}}) or None() instead of the default camera closeup sequence, since it can be very disorienting to take control of the player's camera in VR.