This year marks the 40th celebration of Earth Day. But with green exploding everywhere and a progressive administration in the White House, do we still need it? We asked writers, activists, and business types from around the country to weigh in:

• Nature writer Rick Bass says we need Earth Day more than ever.
• Professional contrarian Dan Akst says Earth Day has become a haven for smug hypocrites.
• Journalist Jennifer Oladipo worries that the Earth Day brand has lost its luster.
• Urban educator Mike Cermak urges greens to look beyond themselves for inspiration.
• Procter & Gamble Sustainability VP Len Sauers says Earth Day is no time for business as usual.
• Gaylord Nelson biographer Bill Christofferson says the Earth Day founder wouldn’t be surprised by the criticism leveled at the holiday — but environmentalists’ work is far from done.