  We present results from ground-based optical imaging of a low-mass dwarf
galaxy discovered by the ALFALFA 21-cm HI survey. Broadband (BVR) data obtained
with the WIYN 3.5-m telescope at Kitt Peak National Observatory (KPNO) are used
to construct color-magnitude diagrams of the galaxy's stellar population down
to V_0 ~ 25. We also use narrowband H-alpha imaging from the KPNO 2.1-m
telescope to identify an HII region in the galaxy. We use these data to
constrain the distance to the galaxy to be between 1.5 and 2.0 Mpc. This places
Leo P within the Local Volume but beyond the Local Group. Its properties are
extreme: it is the lowest-mass system known that contains significant amounts
of gas and is currently forming stars.
