Twistors in Mathematics and Physics

1. Twistor theory after 25 years - its physical status and prospects R. Penrose; 2. Between integral geometry and twistors S. G. Gindikin; 3. Generalized conformal structures S. G. Gindikin; 4. Riemannian twistor spaces and holonomy groups F. E. Burstall; 5. Twistors, ambitwistors, and conformal gravity C. R. LeBrun; 6. The Penrose transform M. G. Eastwood; 7. Notation for the Penrose transform E. G. Dunne; 8. The twistor transform E. G. Dunne and M. G. Eastwood; 9. Invariant operators R. J. Baston and M. G. Eastwood; 10. Penrose's quasi-local mass K. P. Tod; 11. The sparkling 3-form, Ashtekar variables and quasi-local mass L. J. Mason and J. Frauendiener; 12. Twistor and strings W. T. Shaw and L. P. Hughston; 13. Integrable systems in twistor theory R. S. Ward; 14. Twistor characterization of stationary axisymmetric solutions of Einstein's equations J. Fletcher and N. M. J. Woodhouse; 15. A two-surface encoding of radiative space-times C. N. Kozameh, C. J. Cutler and E. T. Newman; 16. Twistors, massless fields and the Penrose transform T.N. Bailey and M. A. Singer; 17. Twistor diagrams and Feynman diagrams A. P. Hodges; 18. Cohomology and twistor diagrams S. A. Huggett; Authors' addresses.