Is government regulation the best?

Many of the students in our resources class say that government regulation is better than either liability rules or private negotiation for dealing with large scale environmental issues, whether involving one large polluter or many small polluters. While I agree to an extent, here's a news flash: government regulation may or may not get the job done. I worked for a year or so for the Environmental League of Massachusetts examining implementation of that state's Toxics Use Reduction Act, and at least half of the work called for in that law had simply not happened. At the Federal level, "stuff" happens, too: here's an example from today's NYT that shows the EPA being overwhelmed by politics. How often do you think Congress acts based on the recommendations of experts, and when they do, how much of the time do you think Congressional acts get the job done? Sometimes they come through for us, but it's not easy to develop and implement effective policy!