In this paper, the authors propose a new process for the development and operation of unmanned vehicles for the exploration of space. We call the vehicle (and the process used to create it) sciencecraft. A Sciencecraft is an integrated unit that combines into a single system those elements (but no more) which are necessary to achieve the science objectives of the mission, including science instruments, electronics, telecommunications, power, and propulsion. The design of a sciencecraft begins with the definition of the mission science objectives. This is followed by the establishment of measurement goals and the definition of a critical data set. Next an observational sequence is developed, which wifi provide the data set. This step is followed by the design of the integrated sensor system that will make the observations. The final step in the development of a sciencecraft is the design of the hardware subsystems needed to deliver the sensor to its target and return the science data to the earth. This approach assures that the sciencecraft hardware design and overall architecture will be driven by the science objectives and the sensor requirements rather than the reverse, as has historically been the case. Throughout the design process, there is an emphasis on shared functionality, shared redundancy, and reduced cost. We ifiustrate the power of the sciencecraft approach by describing the Planetary Integrated Camera Spectrometer (PICS), an integrated sensor system in which the "sciencecraft" process has been applied to the development of a single subsystem, which integrates multiple functionalities. PICS is a case-in-point where the sciencecraft process has been successfully demonstrated. We then describe a sciencecraft mission for exploration of the outer Solar System, including flybys of Uranus, Neptune, and an object in the Kuiper Belt. This mission, called the Kuiper Express, will use solar electric propulsion to shape its trajectory in the inner solar system and will use no nuclear power. The Kuiper Express is an example of how the sciencecraft approach can return "Voyager class science at ten cents on the dollar." 22 / SPIE Vol. 2810 0-8194-2198-7/96/$6.00 I. The Sciencecraft Concept In this paper, we propose a new process for the development and operation of unmanned vehicles for the exploration of space. We call the vehicle Sciencecraft to distinguish it from the more traditional and familiar spacecraft. A Sciencecraft is an integrated unit that combines into a single system those elements (but no more) which are necessary to achieve the science objectives of the mission. This new concept has been made possible by recent advances in technology, especially by the advent of new dense packaging, low power electronics, and lightweight integrated instrument systems. These capabilities lead to the integration of function, lower mass, lower cost and a shortened development cycle. The key to the sciencecraft concept is the new process by which missions are developed (Figure 1). A sciencecraft mission begins with the formation of an integrated mission team of scientists and engineers. This team's first task is to define science objectives and measurement goals, leading to the definition of a critical data set. An observational sequence and the conceptual design for an integrated sensor system are then agreed upon. Only after the sensor system is defined is the design of the science-craft hardware subsystems begun, e.g., electronics, power and propulsion subsystems and thermal and structural design. In this way, hardware design is driven by the science objectives and the sensor requirements rather than the reverse. This is an iterative process in which cost and schedule considerations are introduced, often resulting in adjustment of the observational sequence. The result is a highly integrated vehicle, in which the hardware is matched to the observational goals and non-functional redundancies are minimized or eliminated.