" 'What's hot right now are voluntary environmental programs,' says Jorge Rivera, assistant professor at the George Washington University business school. Mandatory environmentalism is 'effective, but expensive,' Rivera says, and it often produces nothing but 'greenwashing,' where companies satisfy the letter of the law as quickly and as cheaply as they can rather than making a serous effort to innovate. (In some cases, this actually means an increase in environmental damage, as when harmful emissions are converted to less-regulated but more harmful forms.) And since 'a lot of the big, obvious stuff has already been done,' Rivera notes, it isn't really effective to mandate uniform change to bring about marginal gains. So to ward off excessive regulation, help the bottom line, and get brownie points at the same time, companies started playing nice with environmental groups."