How effective are environmental management systems?

Obtaining certification to ISO14001 or the EC eco-management and auditing scheme (EMAS) is now regarded as an obvious first step for companies seeking to demonstrate a commitment to reducing environmental impact. But do these schemes deliver the kind of continuous performance improvement expected? Two European studies suggest that the early answer is "not necessarily" - and highlight the importance of benchmarking companies' performance to find the factors that really make a difference.