A scientific introduction to the management of ambient air : from SO2 to PM2.5 / Vittorio Boraldi and Luisa Guerra -- The protection of air quality in the city of Modena / Giovanni Franco Orlando ; Ambient air quality in town and region : the role of a special company / Vanni Bulgarelli ; Implementing European policy and law : Emilia Romagna / Lino Zanichelli -- The legal framework for the protection of the environment against transboundary air pollution : a reflection on customary and treaty law / Phoebe Okowa -- EC legislation on air pollution : from guidelines to limit values / Massimiliano Montini -- Modern approaches to enforcing community environmental law : a special focus on direct effect and criminal sanctions / Arie Trouwborst -- Air quality : a breathtaking directive? / Marco Gasparinetti -- The future of ambient air management : concluding remarks / Harry Post