Talk about the power of smart investing.

A $3-million gift from millionaire oil man Bill Selby to form the William G. and Marie Selby Foundation 50 years ago this month-and a subsequent $16-million gift made after his wife's death in 1971-have yielded $76 million in grants to 359 area nonprofit organizations. Even more impressive, the private Selby Foundation does not accept donations, as community foundations do; all this has sprung from the Selbys' original $19 million.

It's hard to drive around town without acknowledging the Selby legacy: the downtown Selby Library, Selby Five Points Park, Selby Preschool at Children's Haven, Selby Gallery at the Ringling School of Art and Design and, of course, the Marie Selby Botanical Gardens. The Van Wezel, Mote, G. WIZ, Historic Spanish Point, the Ringling and South Florida museums, Loveland Center and scores of other cultural and human service organizations have benefited from the Selbys' largess-primarily bricks and mortar grants. In addition, some 3,500 students have received $11 million in Selby Scholar higher education grants over the past 50 years.

Down-to-earth Bill and Marie Selby were as different as night and day from the other Sarasota "power couple" of the 1920s, John and Mable Ringling. Rather than building a palatial testament to their good fortunes, like the Ringlings did with Cà d'Zan, the Selbys built a humble Spanish-style home on the bayfront peninsula Marie later bequeathed to the Marie Selby Botanical Gardens. (Today, Selby Gardens uses the historic Selby house for its café and photo gallery.) No celebrity-studded soirees for the Selbys; they preferred the outdoor life-fishing, boating, horseback riding and growing roses. Not only was Marie Selby the first woman to cross the continental United States by automobile, she was team mechanic.

The far-sighted Selbys established their foundation to last in perpetuity, and to ensure that, its board of directors reviews its investment objectives throughout the year and modifies them with the advice of its investment manager, Wachovia, says foundation president Debra Jacobs. Currently, the foundation distributes about $3.5 million each year.

Like many foundations across the country, which saw declines in the value of their investments with the downturn of the stock market in the early part of this decade, "ours dipped during the tumultuous years," Jacobs says. The Foundation's assets, she says, are invested in a blend of equities, fixed income and cash equivalents. "Our investment objective is to seek a return that covers the CPI plus 5 percent," she says. "If we distribute 5 percent each year and have returns that exceed the CPI, then we are keeping pace with inflation and in compliance with our granting requirements."

"If there has been a theme to our modifications in strategy," she says, "it is to look for prudent ways to diversify."

The Selby Foundation will celebrate its 50th anniversary in May and June with luncheons, library displays, free admission Saturdays in June at seven venues that have received Selby grants, and the like. It also will match all Season of Sharing Fund donations dollar for dollar, up to a total of $50,000, between June 1 and Aug. 30. And it has put out a call to past Selby Scholars to compete for one of four $10,000 grants to be awarded to an area nonprofit organization of their choice.

Jacobs likes to cite one of our founding fathers, Benjamin Franklin, when he created the Philadelphia Fund in 1790. "He left 2,000 pounds sterling and today the investment is valued at well over $100 million," she says. "Creating a foundation is indeed a gift that keeps on giving."