The objective of the project is to explore under which circumstances planet “engulfing” or “ingestion” occurs in the host stars of planetary systems. Do passing stars link planets gravitationally into orbits ending in the host stars, and thus cause destruction of the planets and pollution of the surface layers of the hosts? These possible phenomena have been explored in a number of ways, including observations of stars which seem rich in planetary material, and in the present project by numerical studies of the dynamics of planetary systems perturbed by passing stars.. We have set up a many-body simulation code, a modified Gauss-Radau-program of Everhardt (1985), to explore systems with planets and stars under mutual gravitational interaction. In addition to this we have modeled the statistical fluctuation of the gravitational potential in rich stellar fields by our own codes. We have also initiated studies of planetary systems in binary stars, where the tidal effects from a star may link planets into the other stellar component.