Non-accelerator particle physicists, especially those studying neutrino oscillation experiments, will read with profit the in-depth discussions of new results and their interpretations. new guidelines are also set out for new developments in this and related fields. Discussions are presented of neutrino oscillations, neutrino astronomy, high energy cosmic rays, gravitational waves, magnetic monopoles and dark matter. The future large-scale research projects discussed include the experiments on long baseline neutrino beams from CERN to Gran Sasso and Fermilab to the Soudan mine; large underwater and under-ice experiments; the highest energy cosmic rays; gravitational waves; and the search for new particles and new phenomena.Proceedings of the NATO Advanced Research Workshop held in Oujda, Morocco, 18-20 October 2000Non-accelerator particle physicists, especially those studying neutrino oscillation experiments, will read with profit the in-depth discussions of new results and their interpretations. new guidelines are also set out for new developments in this and related fields. Discussions are presented of neutrino oscillations, neutrino astronomy, high energy cosmic rays, gravitational waves, magnetic monopoles and dark matter. The future large-scale research projects discussed include the experiments on long baseline neutrino beams from CERN to Gran Sasso and Fermilab to the Soudan mine; large underwater and under-ice experiments; the highest energy cosmic rays; gravitational waves; and the search for new particles and new phenomena.Contents. 1. Overview. Puzzles in Astrophysics; V. Berezinsky. Status of Neutrino Physics; J.W.F. Valle. 2. Gravitational Waves. Gravitational Waves; B.C. Barish. Energetic Cosmic Rays Observed by the Resonant Gravitational Wave Detector NAUTIILUS; F. Ronga. 3. Magnetic Monopoles. Magnetic Monopoles; G. Giacomelli, L. Patrizii. Monopole Catalysis of Nucleon Decay: Theory and Experimental Results; M. Sitta. Sl£*