The thesis is entitled "The Role of the Yogyakarta City Transportation Department in Preventing Air Pollution Through Motorcycle Emission Tests". Population density in Yogyakarta City is followed by the density of vehicles,
especially motorized vehicles. The number of motor vehicles can result in air pollution produced by emissions emitted. Every motor vehicle is required to carry out emission tests carried out by the Department of Transportation. In order to
answer these problems, the author uses empirical research methods, namely research that focuses on social or field facts. As a result, the reviewer knew that the Yogyakarta City Transportation Office had done its duties and authorities well.
However, the obstacle faced is the low awareness of motorized vehicle owners to
conduct emission tests so that air pollution in Yogyakarta City is increasing and is
now included in the yellow category.