This article presents the development and results of Ozone Web—a near-real-time Web-based approach to communicate environmental information to policy makers, researchers, and the general public. In Ozone Web, ground-level ozone information from 750 air quality measurement stations across Europe is collected on an hourly basis, filtered, interpolated, and presented on zoomable maps and graphs. Compared with other environmental information initiatives, the main aspects of this Website is the allowance for user interactivity, free access to data, and high timeliness. Data are published 2 to 3 h after actual monitoring. In a response to the acute characteristics of air pollution, the basic principle is that up-to-date and accurate information about air pollution levels will help 1) citizens to protect their health, 2) policy makers in assessing the state of the environment, and 3) researchers in exchanging data and knowledge. Near-real-time information systems on the Web seem to be a valuable complement to future environmental reporting, and the European Environment Agency is currently investigating the requirements needed to extend the use of near-real-time data, including reporting on air pollutants other than ozone.