Perhaps it was the smell of Oriental Woods. Or the scent of Midnight Blossom. Regardless, when Elton John first stepped into Harry Slatkin's Manhattan candle boutique in '94, he dropped thousands of dollars before he left. "We didn't close the shop for anyone," says Slatkin, 44, "but we did for him."

Celebrities have been like moths to the flame after Slatkin, at the urging of his designer friend Vera Wang, launched Slatkin & Co. in '92 with his wife, Laura, 46. His products, available at Neiman Marcus and soon to be sold in Bath & Body Works and Victoria's Secret, have attracted clients like Princess Diana and Oprah Winfrey. And he created a line of Kabbalah candles for the likes of Madonna and Demi Moore. Says John, who hired Slatkin to produce candles for his AIDS Foundation: "Harry has a real eye for detail."

But many know him more for his heart. Eighteen months after their now-5-year-old twins, David and Ali, were born, the Slatkins learned that David was severely autistic and unable to talk. They have since poured their energy—and thousands of dollars—into autism efforts. In '02 they launched the New York Center for Autism, a foundation promoting education, research and support. In April they won approval for a New York City charter school for autistic kids, which they hope to open this fall. But Slatkin looks to David for a bigger success: "I just want to hear one word," he says." 'Daddy.' "