After 33 years as a school psychologist with the New York Board of Education, Ralph Rosenberg retired in 2001, and although he was only 55, he was already thinking about his legacy. He considered selling a studio apartment he owned and donating the profits to a charity. He had bought the apartment, in the Kips Bay section of Manhattan, as an investment property for $64,000 in 1983. But when he had it appraised in 2000, it was worth more than $200,000.

Reeling from the capital-gains tax that he would have to pay, Mr. Rosenberg decided to donate the studio to the UJA-Federation of New York, a nonprofit group that finances health, social service, education and community programs.

"After I donated it, they took over the property and they sold it," he said. "The proceeds went into a charitable trust. They invest that. I was able to make a maximum donation and get tax benefits."

In the late 1990's, appreciated stocks were the preferred form of noncash donations, but now, with the real estate market appreciating more steadily than the stock market, fund-raisers are showing increased interest in summer homes, ski cottages and apartments.

Individuals donated an estimated $180 billion to charities in 2003, according to Giving USA, the name of an annual report by the Center on Philanthropy at Indiana University in Indianapolis. Of that, experts say that only a small percentage comes from real estate donations. With real estate accounting for 29 percent of total household assets in the United States, it is one of the last untapped sources for charitable giving, said Dennis Bidwell, the principal of Bidwell Advisors, a real estate gift planning firm in Northampton, Mass.

"Real estate is one of those assets that have represented increasing value," said Charles Goldman, group vice president for planned giving and endowments at UJA-Federation, who assisted Mr. Rosenberg's donation. "The stock market has been so volatile. We're out there talking about gifts of real estate."

In Mr. Rosenberg's case, the apartment was placed in a trust, which sold it for $216,000 in one week. This allowed him to avoid capital gains and receive a charitable donation tax deduction on the assumed value to the charity.

The money from the sale of the apartment was placed in a charitable remainder unitrust, a diversified fund revalued annually, and Mr. Rosenberg draws a fixed 7 percent rate from it yearly until his death, when the assets will go to the UJA-Federation. He was also able to earmark 25 percent of his gift for the American Cancer Society upon his death, a cause close to him because his parents died of cancer.

"A lot of people in my generation, we were very idealistic, but we had to meet financial demands for family and self," Mr. Rosenberg said. "Now is a good time to give back."

For institutions, gifts of real estate can be more challenging than cash or stocks. While some organizations may have use for a donated property, the most beneficial action for both donor and institution is usually to sell it. But the property has to clear some criteria: it must have appreciated in value and not been on the market for a long time; it must also , be marketable and environmentally sound. While the property can be accepted with an outstanding mortgage, donors may have a harder time finding an institution that is willing to accept it.

As Dan Chegwidden, director of planned giving at Michigan State University in East Lansing, put it: "Gifts of real estate are sort of like the forward pass in football. Two out of the three things that can happen are bad: it can be dropped or it can be intercepted. Or it can be caught."

Mr. Chegwidden said that his office now accepts less than 15 percent of the real estate that comes its way. Fifteen years ago, he said, the number was higher. "We had property that sat around for years and years until we finally sold it, because we weren't very sophisticated," he added.

Anna Bahney, New York Times