"This project concerns the further development and exploration of new calculational technology for quantum field theory in mainly four dimensions based on the mathematics of its associated twistor space. The applicant was involved in some promising initial steps in this direction initiated in Oxford. As quantum field theory is a 'language' which has an extremely wide range of applications, this technology has the potential of having an impact in several areas of physics and mathematics. Three broad directions within high energy physics are singled out in the proposal: - Streamlined perturbative calculations (some directly relevant for collider experiments) - Non-perturbative applications through Seiberg-Witten theory - Investigation into the application of twistor techniques within the so-called AdS/CFT correspondence For a successful project along these lines, it is essential that the research is embedded in an environment with a broad range of interest and expertise in high energy physics. The Niels Bohr institute represents such an environment."