A **Department** is an entity within the [[Foundation (CSDM domain)|Foundation domain]] of the [[Common Service Data Model|Common Service Data Model]] (CSDM), a reference architecture developed by [[ServiceNow|ServiceNow]] that provides prescriptive guidance on service-related definitions and data modeling within the ServiceNow AI Platform. A Department represents a further stratification of [[Business Unit (CSDM)|Business Units]], providing another way to categorize [[User (CSDM)|users]], [[Group (CSDM)|groups]], [[Asset|assets]], and [[Configuration item|configuration items]] within the organizational structure. Departments are recorded in the cmn_department table and are part of the [[Common Data (CSDM)|Common Data (CSDM)]] that is shared throughout the ServiceNow AI Platform. Departments are not configuration items but serve as critical referential data that multiple ServiceNow products depend upon for reporting, workflows, and [[Artificial intelligence|AI]] agents. When planning Common Data, organizations should consider whether they have a trusted source for department data, how often the data changes, whether the depth of data meets CI requirements, and who will maintain the data. ServiceNow recommends establishing Department data as part of the Foundation stage of [[CSDM Adoption Stages|CSDM adoption]], as early planning around organizational structure helps avoid costly rework when aligning data to reporting requirements across the [[CSDM Service Life Cycle|CSDM Service Life Cycle]].