  Geodesy in a Newtonian framework is based on the Newtonian gravitational
potential. The general-relativistic gravitational field, however, is not fully
determined by a single potential. The vacuum field around a stationary source
can be decomposed into two scalar potentials and a tensorial spatial metric,
which together serve as the basis for general-relativistic geodesy. One of the
scalar potentials is a generalization of the Newtonian potential while the
second one describes the influence of the rotation of the source on the
gravitational field for which no non-relativistic counterpart exists. In this
paper the operational realizations of these two potentials, and also of the
spatial metric, are discussed. For some analytically given spacetimes the two
potentials are exemplified and their relevance for practical geodesy on Earth
is outlined.
