after a vacancy is made available due to transfer or retirement of a pre-existing sergeant. Senior constables must first successfully complete the Sergeant Level Pre-promotional Qualifying Exam. A sergeant normally manages a team during a shift, like Patrol Supervisor of a Police Service Area (PSA) for a shift. A detective sergeant is typically in charge of a team in a specific part of either local detectives at police stations or crime squads. A senior sergeant oversees the sergeants and traditionally performs more administrative work and middle management duties, for example coordination of policing operations, or specialist work other than active patrol duties. General-duties senior sergeants are traditionally in charge of most police stations or can be a sub-charge (or second in charge) of larger (usually 24-hour) police stations. In each division, or group of divisions on a night shift, a senior sergeant is the division supervisor for a shift and is responsible for managing and overseeing incidents in their area. Detective senior sergeants are usually the officer in charge of crime investigation units. Designations Additional classifications are available for officers skilful enough, and upon completion of certain training and work-based performances, for classification of detective at senior constable level. Detectives also hold classification up to superintendent. Structure Victoria Police divides the state into four geographic regions with each region allocated dedicated resources and each region is commanded by an Assistant Commissioner. The regions are: Eastern Region North West Metro Region Southern Metro Region Western Region Victoria Police has the following departments and commands that service the whole of Victoria: Capability Department Counter Terrorism Command Crime Command Family Violence Command Financial Services Department Forensic Services Department Gender Equality & Inclusion Command Governance and Assurance Department Human Resource Department Information Systems & Security Command Intelligence & Covert Support Command Investment Management & Reporting Department Legal Services Department Media & Corporate Communications Department Operational Infrastructure Department People Development Command Police Enquiry & Data Sharing Department Professional Standards Command Regulatory Services Department Road Policing Command State Emergencies & Support Command Transit & Public Safety Command Protective Services Unit The Protective Services Unit (PSU) was established in 1986 following a security review. The first deployment of a Protective Services Officer (PSO) was on 1 May 1988. The PSU has two divisions: Security and Transit. PSU is part of Transit and Public Safety Command (TPSC), along with the Dog Squad, Mounted Branch, Search and Rescue, Special