  In this talk, we report on two recent studies of relativistic nucleon-nucleon
and hyperon-nucleon interactions in covariant chiral perturbation theory, where
they are constructed up to leading order. The relevant unknown low energy
constants are fixed by fitting to the nucleon-nucleon and hyperon-nucleon
scattering data. It is shown that these interactions can describe the
scattering data with a quality similar to their next-to-leading order
non-relativistic counterparts. These studies show that it is technically
feasible to construct relativist baryon-baryon interactions, and in addition,
after further refinements, these interactions may provide important inputs to
{\it ab initio} relativistic nuclear structure and reaction studies and help
improve our understanding of low energy strong interactions.
