  We report the synthesis and physical properties of single crystals of
stoichiometric BaNi2As2 that crystalizes in the ThCr2Si2 structure with lattice
parameters a = 4.112(4) \AA and c = 11.54(2) \AA. Resistivity and heat capacity
show a first order phase transition at T_0 = 130 K with a thermal hysteresis of
7 K. The Hall coefficient is weakly temperature dependent from room temperature
to 2 K where it has a value of -4x10^{-10} \Omega-cm/Oe. Resistivity,
ac-susceptibility, and heat capacity find evidence for bulk superconductivity
at T_c = 0.7 K. The Sommerfeld coefficient at T_c is 11.6 \pm 0.9 mJ/molK^2.
The upper critical field is anisotropic with initial slopes of dH_{c2}^{c}/dT =
-0.19 T/K and dH_{c2}^{ab}/dT = -0.40 T/K, as determined by resistivity.
