Commissioners are also known as the "boss" and is the most senior UK police officer.
Deputy Commissioners have similiar roles/ functions as per Deputy Chief Constable of a Non London force.
There are three AC's, plus an extra, temporary one for the Olympics. They carry similiar responsibilities to ACC's in Non London forces, but on a broader, larger scale. They are equivalent to the Chief Constables.
Larger forces Chief Constables tend to have been CC's elsewhere first.
Deputy Assistant Commissioner
Deputy Assistant Commissioners oversees groups of departments or boroughs in London. There are eight of them.
Deputy Chief Constable
The senior discipline authority for each force and as the name suggests, the 2nd in charge of the force. Has certain policy responsibilities and an overall eye of force performance. One per Non-London force.
Commanders are head of a major department or group of boroughs. These are the first "ACPO ranks" (Chief Police Officers) and some officers have a national lead on certain issues.
Assistant Chief Constable
Between one and five per force, dependent on size. Responsible for a certain policy area forcewide, as well as "territoral" oversight of two or more boroughs.
Chief Superintendents are head of a policing area or headquarters department. They are responsible to the Chief Constable for all policing activity in their area. The person is the "local police chief" to whom all local partnership, crime and operations matters are directed.
Usually one or two on each borough. Responsible for "Operations" or "Crime" or "Partnerships". Also carry a range of particular statutory authorities and also act as senior public order or firearms commanders.
Usually two or three working on any borough. Would oversee "Response Teams" and/or "Police Neighbourhood Teams" or CID/Investigations/Offender Management.
Senior operational officer 24/7. Oversees all officers on duty at that time-there is usually just one "duty Inspector" in operational command at any time.
Sergeants supervise teams of officers, overseeing police operations, volume crime investigations, demand management issues and take initial control of critical incidents.
Officers who turn up to public 999 calls, investigate volume crime or take initial action at critical incidents. Also work on neighbourhood teams to target long term problems.