In this paper, we discuss development of useful intelligent systems, emphasizing an integrated systems perspective. In particular we will highlight two important ideas. The first is associated with the sensor-based control, for realizing effective and robust approaches for processing and analysis of sensory information associated with the state of the environment and the state of the intelligent system for reflexive and deliberative tasks. The second is associated with cooperation, for developing teams consisting of heterogenerous and complementary intelligent modules. The aim is to develop useful and effective intelligent systems involving teams of players which are either all robotic devices or some robotic and some human.