Four case studies have been conducted; for each case study a report describes lessons to be learnt from measures taken. The reports are available here in PDF format.

There is a "shell" report (0.3 MB) containing executive summaries and a reference list for all four case studies.

The individual case studies are the following:

• The EU and US Approaches towards Acidification, Eutrophication and Ground-Level Ozone (5.3 MB).
• EU and US Air Quality Standards and Planning Requirements (1 MB).
• EU and US Approaches towards Controlling Emissions from High-Emitting Vehicles (0.4 MB).
• EU and US Approaches towards Particulate Matter (1.2 MB).