On Tuesday, Leonard Lopate of WNYC interviewed Worldchanging Executive Editor Alex Steffen about the "stickiness" of environmental trends. Leonard wanted to know why environmental trends -- like bringing your own canvas bag to the store -- catch on in some places, and not in others. Laura Haight, senior environmental associate with the New York Public Interest Research Group in Albany, New York, also joined in on the conversation.

So, how do environmental trends spread? How can we improve their chances of sticking? And where does individual responsibility end and government responsibility begin? Listen to find out.