2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/10544The most important sources for laser-interferometric gravitational-wave detectors like LIGO or VIRGO are catastrophic events such as coalescence of a neutron-star binary. The final phase, or the last three milliseconds, of coalescence is considered. We describe results of numerical simulations of coalescing binary neutron stars using Newtonian and post-Newtonian hydrodynamics code and then discuss recent development of our 3D GR code.30 pages, LaTeX, 17 PostScript figures, Lecture delivered at Les Houches School ``Astrophysical Sources of Gravitational Radiation'' (Les Houches, France, Sept. 26 - Oct. 6, 1995). To be published in the Proceedings (eds. J.-A. Marck and J.-P. Lasota)Astrophysicstext