When you select this option, you are allowing your work to be used or viewed by other users within the practice or practices you designate. For example, if you save a custom header as Practice, that header is available for other users to use from the Notes module.
If you are associated with more than one practice, the LMR also prompts you to select the practices that you want to authorize for use of the custom item. To select multiple practices, hold down the CTRL key while clicking.