  We report electronic structure calculations for the layered centrosymmetric
superconductor LaNiGa$_2$, which has been identified as having a possible
triplet state based on evidence for time reversal symmetry breaking. The Fermi
surface has several large sheets and is only moderately anisotropic, so that
the material is best described as a three dimensional metal. These include
sections that are open in the in-plane direction as well as a section that
approaches the zone center. The density of states is high and primarily derived
from Ga $p$ states, which hybridize with Ni $d$ states. Comparing with
experimental specific heat data, we infer a superconducting $\lambda \le$ 0.55,
which implies that this is a weak to intermediate coupling material. However,
the Ni occurs in a nominal $d^{10}$ configuration in this material, which
places the compound far from magnetism. Implications of these results for
superconductivity are discussed.
