The paper presents selection of analytical methods for determination of airborne benzidine, whose maximum admissible concentration (MAC) comes to zero. Colorimetric method with T chloroamine, allowing to determine 3 microgram of benzidine in m3 of the air, was evaluated. Such advantages of the method as specificity and availability of reagents and measuring apparatus were stressed. Another method presented in the paper is based on liquid chromatography, and its main features are: much better determinability of--0.7 microgram benzidine in m3 of the air and better precision than that of the colorimetric method. Its usefulness is however limited due to the necessity to have a very expensive liquid chromatograph.