A method for defining, generating, and using a global back-end taxonomy is disclosed. It is identified that a listing of an item is exposed to a plurality of users of a first subsystem via a set of categories of a first front-end taxonomy. The listing of the item is mapped to a set of categories of a global back-end taxonomy, the global back-end taxonomy being maintained independently of the first front-end taxonomy and a second front-end taxonomy, the second front-end taxonomy being associated with a second subsystem. A category of the set of categories of the global back-end taxonomy is mapped to a category of a set of categories of the second front-end taxonomy associated with the second subsystem. The listing of the item is exposed to a plurality of users of the second subsystem via the set of categories of the second front-end taxonomy.