When Barack Obama stood in front of 2 million people to make his inaugural speech in January, the word trust was in the very first sentence to come out of his mouth.  Makes sense. Trust has been in short supply in Washington in recent years, thanks to increased partisan bickering during the election campaign and wounds that are still raw from the war in Iraq and the debate over whether it ever should have been waged.

In business, the erosion of trust is, if possible, even worse. Institutions and executives once seen as solid have been called into question. (Who knew John Thain had such an eye for interior design? Why did Apple keep changing its explanation of Steve Jobs’ illness?) Investors have been wiped out. Corporate balance sheets have been exposed as fraudulent.

Bernie Madoff turned the trust of some of the world’s savviest financial players toxic. He tapped connections to give his investment scam a velvet-rope feel, somehow convincing people that they were lucky to be in business with him. The novelist Scott Turow, in an essay opening this issue of Condé Nast Portfolio, argues that Madoff’s betrayal of his investors’ trust makes him the poster boy for our age of arrogance, which is finally now winding down.

But Turow also identifies an upside to Madoff and to the financial meltdown—an opportunity for reform that could become the more enduring legacy of the recent crisis. “The assumptions underpinning the American economy have not been as open to restructuring since Franklin D. Roosevelt entered the White House,” Turow writes.

These opportunities for change play into the themes that Portfolio has championed since our own inauguration nearly two years ago: greater transparency, the benefits of effective regulation, a distrust of financial fads. Contributing editor Gary Weiss, in “Preventing the Next Madoff,” argues that ending Wall Street’s cycle of scandal will mean radically rethinking how to fix the problem. In search of a solution, he studied the police corruption scandals of the 1970s, drawing fascinating parallels with where we are in finance today.

Contributing editor David Margolick investigates another crisis of trust in “Slimed Online,” an astonishing look at the vicious world of online bullying. In the incidents Margolick chronicles, the cyber-thugs’ victims are not teenagers tapping away in dark basements but Yale Law School students, the best of their classes. The attacks on the students have prompted a lawsuit that could test the limits of free speech on the internet.

Questions about the limits of the Web are among the issues we fully expect some of the people on our Tech 25 list to tackle. The list is our first annual tally of the individuals who have had the most tech-related influence—for better or for worse—on the industries they work in or deal with. It ranges from Rex Tillerson, the anti-green-energy executive at Exxon Mobil, to blog queen Arianna Huffington and the founders of Google. As contributing editor Peter Waldman explains in “Google’s Power Play,” the search giant is starting to use its moxie to address issues with the nation’s energy supply—a move that could change how we use electricity.

Then there’s Joe Rospars, the twenty-something new-media whiz credited with transforming the president’s political campaign. Rospars made the Tech 25 because he helped Obama use Facebook, MySpace, and Twitter to win the trust of young voters who were turned off by politics. Now young voters are more enthusiastic and engaged than at any time since the 1960s.

The same thing can happen in business and on Wall Street. The rebuilding begins now.