  Using the multiconfiguration Dirac-Hartree-Fock (MCDHF) and the relativistic
configuration interaction (RCI) methods, a consistent set of transition
energies and radiative transition data for the lowest 150 states of the $3s^2
3p^3$, $3s 3p^4$, $3s^2 3p^2 3d$, $3s 3p^3 3d$, $3p^5$, and $3s^2 3p 3d^2$
configurations in P-like Ge XVIII is provided. To assess the accuracy of the
MCDHF transition energies, we have also performed calculations using the
many-body perturbation theory (MBPT). Comparisons are made between the present
MCDHF and MBPT data sets, as well as with other available experimental and
theoretical values. The resulting accurate and consistent MCDHF data set will
be useful for line identification and modeling purposes. These data can be
considered as a benchmark for other calculations.
