The Cambridge Center is pleased to present this third installment in our Continuing Education (CE/CEU) series, a fascinating look at the way operant research labs have used and evolved technology in the development of our science of Behavior Analysis. Andy Lattal presented this to the Cambridge Center at our annual Trustees meeting in 2006, and he consented to present it in front of our cameras in San Diego on May 29, 2007, the closing day of the ABA conference. Andy makes some very good points about the interaction of our instrumentation and our conceptual understanding of behavior. We measure only what our apparatus allows us to, and in the beginning it required an inventor’s skill set to be to present stimuli and measure behavior while manipulating contingencies of reinforcement. The advancement of instrumentation and apparatus has led to more sophisticated questions about behavior as it has become possible to measure it. The evolution of behavioral technology both enables and reflects our scientific interests.