At 15, Haitao Zheng stood out at Chinas competitive Xian Jiaotong University for both her youth and her brilliance. Today, her work on so-called cognitive radios stands out for its potential to make a promising technology practical. Using software, cognitive radios dynamically detect and exploit unused radio frequencies; the devices could alleviate competition for the ever shrinking amount of unassigned radio spectrum. To be truly useful, though, a cognitive radio must not only detect free spectrum but also select the best frequency for a given function, all without interfering with other devices. At Microsoft Research Asia, Zheng created algorithms that allow disparate devices to "negotiate," automatically allocating the available spectrum efficiently and fairly. Zheng is continuing her research on open spectrum systems as an assistant professor of computer science at the University of California, Santa Barbara.