  We construct a complete action for open superstring field theory that
includes the Neveu-Schwarz sector and the Ramond sector. For the Neveu-Schwarz
sector, we use the string field in the large Hilbert space of the
superconformal ghost sector, and the action in the Neveu-Schwarz sector is the
same as the Wess-Zumino-Witten-like action of the Berkovits formulation. For
the Ramond sector, it is known that the BRST cohomology on an appropriate
subspace of the small Hilbert space reproduces the correct spectrum, and we use
the string field projected to this subspace. We show that the action is
invariant under gauge transformations that are consistent with the projection
for the string field in the Ramond sector.
