1 Introduction

This document specifies the Custom UI XML Markup Version 2, which is used to implement UI customization in the context of the standards for Microsoft Office Open XML file formats as described in [ISO/IEC29500:2012]. Examples in this document describe customizations in the context of the Microsoft Office Fluent interface (UI), which includes the ribbon, Quick Access Toolbar, context menus, and Microsoft Office Backstage view, but the concepts extend naturally to any user interface.

Sections 1.7 and 2 of this specification are normative. All other sections and examples in this specification are informative.