This article reports on the Zurich Aircraft Noise Index (ZFI), a noise eff ect index describing the integral eff ects of aircraft noise (annoyance and sleep disturbance) on the population in the vicinity of Zurich airport, integrating the considered noise eff ects to a single number valid for the whole airport. In the year 2007 the ZFI became operational as an eff ect-oriented monitoring tool serving noise abatement policy in the canton of Zurich, Switzerland. During its development, various exposure-response relationships and parameter settings were studied as a basis to establish the official calculation rule. The official calculation rule was then applied to a time series of 12 years, and reasons for changes in the ZFI were studied by means of sensitivity analyses, taking into account the air traffic operations and population development around Zurich airport in great detail. The article presents the concept and implementation of the ZFI, its development, its application, and insights obtained so far. Based on the obtained results, the potential and limitations of the index to express the number of aff ected persons, its sensitivity to changes in population figures and air traffic as well as the possibilities to separate diff erent influencing parameters, and the scientific shortcomings of the index are discussed.