  Phi meson production in pion-baryon and baryon-baryon interactions near the
production threshold is studied in a boson-exchange model. Parameters in this
model are either taken from the Bonn model for the nucleon-nucleon potential or
determined from the measured phi meson decay width and the experimental data
for the reactions $\pi^-p\arr \phi n$ and $pp\arr pp\phi$. The isospin-averaged
cross sections for the reactions $\pi N\arr \phi N$, $\pi \Delta \arr \phi N$,
$NN\arr NN\phi$, which are needed in transport models to study phi meson
production in heavy-ion collisions at subthreshold energies, have been
evaluated. For the reactions $N\Delta\arr NN\phi$ and $\Delta\Delta\arr
NN\phi$, which become singular when the exchanged pion is on-shell, the Peierls
method is used to calculate their cross sections. We find that the cross
section for the reaction $\pi N\arr\phi N$ is much larger than the other cross
sections.
