Leaders of several large investment firms have issued a stern warning to companies that ignore social and environmental responsibilities: their share prices may fall.

The Global Compact summit brought together more than 400 business and government leaders to discuss better corporate practices in human rights, labor and the environment.

They heard U.N. Secretary General Kofi Annan speak of working toward a future in which the gap between rich and poor grows narrower and where globalization provides opportunities for all.

But one of the hottest topics among those in attendance was how to reconcile corporate responsibility with the need to increase share prices.

Espen Klitzling of the Norwegian investment group Storebrand said recent studies indicate that environmental, social and corporate governance issues clearly affect long-term shareholder value.

"The report in our view provides strong independent support for the view that effective management of these issues will contribute to improved shareholder value," he said. "It's not just about being a good citizen, it's actually about achieving superior returns."

Mr. Klitzling and other executives announced that 20 financial institutions would begin promoting U.N.-backed environmental and labor standards, but they faced a barrage of skeptical questions when they unveiled plans to voluntarily work against corruption in all forms, including extortion and bribery.

Anthony Ling of the Wall Street investment firm Goldman-Sachs conceded that recent corporate scandals have made cynics of many.

"Nothing I can say right now that can effectively change your mind," said Mr. Ling. "I think what you see is that CEOs of 20 institutions have effectively endorsed this initiative tells you this is not something to do with bleeding heart liberalism or an exercise in PR. This is something we genuinely believe it."

Across town, a smaller group of skeptics gathered for a counter summit sponsored by the environmental group Greenpeace. Kenny Bruno of Earth Rights International scoffed at the concept of voluntary corporate responsibility. He accused participants at the U.N. conference of using the world body as a shield while they carry on business as usual. He said, "In our opinion, business is getting to wrap itself in the blue flag of the United Nations, to blue-wash its image and they aren't giving a whole lot back to the U.N."

Participants at the counter-summit say the Global Compact represents only a handful of the 60,000 transnational corporations doing business. They called for establishment of mandatory corporate responsibility guidelines.