In the near future, large mechs called Labors are made to assist in various reconstruction projects in major countries around the world that are being threatened by global warming. In Japan, the government has enacted Project Babylon in order to conduct land reclamation. Labors are also being pressed into police and military service aside from civilian use. 
However, terrorists are now attempting to use labors to make themselves heard, as well as common criminals, thugs and guerrillas. The National Police Agency established the Special Vehicles Division, an all-labor task force to combat the potential use of labors for criminal/terrorist activities.
 
Note: The chapter count reflects the manga's total number of chapters that were published originally in the Shounen Sunday magazine.

In the future, rapidly advancing technology gives birth to giant robots known as "Labors," so named for their usefulness in heavy industry. However, this also gives rise to "Labor crimes," resulting the need for a new branch of law enforcement equipped with and dedicated to the policing of Labors. When Izumi Noa, a female police officer, becomes the newest recruit of Special Vehicles Division 2, she and her top of the line "Patrol Labor" (or "Patlabor") Alphonse are swept into a series of adventures featuring crazed construction workers, eco-terrorists, and sea monsters. 
(Source: Anime News Network)

In the future, advanced robotics has created heavy robots ("labors") for use in a variety of functions: construction, fire-fighting, military, and more. However, though the robots are only machines, their operators are also only human - and humans sometimes turn to crime. Since a heavy labor unit can be a dangerous weapon, the police of the future are set to fight fire with fire, using advanced patrol labor units, "patlabors". This is the story of the Second Special Vehicles Division, a motley crew of patlabor policemen and -women doing their best to fight crime and live a normal life. 
(Source: Anime News Network)

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