Air pollution, one of the most critical environmental and health challenges, causes millions of premature deaths annually. Transportation, especially internal combustion vehicles, is a significant source of pollutants such as particulate matter, nitrogen oxides, carbon monoxide, and hydrocarbons. This article analyzes methods for measuring exhaust emissions in laboratories and real-world operating conditions, discussing their advantages and limitations. Traditional dynamometer tests conducted on test benches enable detailed analyses but do not fully reflect real-world operating conditions. These tests fail to account for factors such as driving style or variable weather conditions. Modern methods, such as Real Driving Emissions (RDE) tests using Portable Emissions Measurement Systems (PEMS), allow for emission measurements in real traffic conditions, although they are costly and time-consuming. Alternative approaches for measuring emissions during transit, such as remote sensing (tunnel, extractive, or open-path methods), enable quick and efficient studies on large vehicle samples, though they come with certain limitations, such as result precision or the influence of external conditions. The article also highlights research on rail vehicle emissions, which remain limited to laboratory engine tests. This underscores the need for further development of measurement technologies and the implementation of more advanced methods for better emission monitoring. Measurements play a crucial role in designing policies aimed at reducing pollution, such as low-emission zones or stricter exhaust emission standards. This is of critical importance for achieving climate goals, such as carbon neutrality.