Extensible architecture for template-baser user setting management by creating logical groupings of per-user settings using different template types. A manageable way to assign templates to sets of users based on different criteria is provided. Templates can be defined in a declarative format (e.g., XML), which declarative format is developed such that various user interface (UI) pieces, third-party applications, and different client types can easily understand the templates. Extensibility of the architecture is supported for defining the templates such that external third-party application writers can make use of the provided infrastructure to add to existing templates or create new template types, and to seamlessly integrate into the existing infrastructure. Additionally, the per-user settings within the templates can be enforced on the server side, including the enforcement of future settings and template types.