# Multi-Site Manager Advanced Categories works in an MSM install, however, there are some things to be aware of. * ExpressionEngine lets you share custom fields across multiple sites. * ExpressionEngine does not let you share category groups across sites. For those reasons, and based on what Advanced Categories is intended to do, you can not share an Advanced Category field across multiple sites. You will need to make an Advanced Category field unique to each MSM site you are running. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.boldminded.com/advanced-categories/docs/setup-and-configuration/multi-site-manager.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.