According to the St. Baldrick's site, this is how the foundation got its start:
On March 17, 2000, reinsurance executives John Bender, Tim Kenny and Enda McDonnell turned their industry's St. Patrick's Day party into a head-shaving event to benefit kids with cancer. Their 20 "shavee" recruits planned to raise "$17,000 on the 17th." Instead, they raised over $104,000!
The movement quickly grew into the world’s largest volunteer-driven fundraising program for childhood cancer research, and today the St. Baldrick's Foundation funds more in childhood cancer research grants than any organization except the U.S. government. Since 2000, more than 189,660 volunteers -- including over 17,200 women -- have shaved in solidarity with children with cancer at events in dozens of countries and every U.S. state. Thanks to generous friends and family, these shavees have raised over $117 million for life-saving research, and each is a walking billboard for the cause!