BALTIMORE, Md., June 4 -- The LEAP program at CLEO attracted standing-room audiences on opening day at CLEO/QELS. Tuesday's program included sessions on optics in biology and medicine and an overview of DARPA-funded optics. The attendance at both sessions illustrated that the photonics community considers both topics areas of future growth. The technologies involved are more closely related than the topics suggest. Both involve sensing or detecting either objects or gasses, and techniques that are used to diagnose medical conditions are not unlike those used to detect toxic substances. Biology and medicine are both old-line applications. What is driving much of the research is the new emphasis on homeland defense. Technologies that were once thought to be only of military significance are now being developed for potential applications in thwarting terrorists. The LEAP sessions drew standing-room-only crowds. As a DARPA presenter said, one could think of biosensors for defense against toxic agents as the equivalent of sprinkler systems used for defense against fires. Such systems could be used not only as stationary installations, such as with springler systems; they could also be flown in micro remote-controlled aircraft. The LEAP program continues Wednesday and Thursday with a keynote speech and sessions on business and management, intellectual property rights and the next big growth areas in photonics.