  We discuss the region of transition between galactic and extragalactic cosmic
rays. The exact shapes and compositions of these two components contains
information about important parameters of powerful astrophysical sources and
the conditions in extragalactic space as well as for the cosmological evolution
of the sources of high energy cosmic rays. Several types of experimental data,
including the exact shape of the ultrahigh energy cosmic rays, their chemical
composition and their anisotropy, and the fluxes of cosmogenic neutrinos have
to be included in the solution of this problem.
