MARTIN: If you're just joining us, we're speaking with Tracy Chapman. She's winding up her U.S. tour in support of her latest album, "Our Bright Future." And speaking, you know, of our bright future and your hopes for our bright future, you've always been known for standing up for causes and identifying yourself with organizations that do work that you believe in like, Amnesty International or AMFAR. How do you decide what you want to get involved in?