Abstract: Metadata is used to create customized user interface (UI) portions for an application. The metadata may be XML-based and can be interpreted and then rendered to implement a customized UI that also supports data binding between data and the UI controls. Once created, the metadata is processed by a rendering engine to display the UI controls. An interpreter may be used to interpret the metadata file before it sent to the rendering engine. Neither the rendering engine nor the interpreter needs knowledge of the host application and provides support for arbitrary metadata driven UI. The metadata schema may include mechanisms to create custom controls for the UI; programmatically modify the UI controls by providing access to a code-behind assembly as well as support event handling for the UI controls.