  Chiral perturbation theory at finite four-volume V (=L^3T) is reconsidered
with a view towards finding a computational scheme that can deal with any value
of M_\pi L, where M_\pi is a generic Nambu-Goldstone mass. The momentum zero
modes that cause the usual p-expansion to fail in the chiral limit are treated
separately, and partly integrated out to all orders. In this way the theory
remains infrared finite in the perturbative expansion, and the chiral limit can
be considered at finite volume. We illustrate the technique by computing the
quark condensate in a finite volume, smoothly connecting standard results in
the p-regime for larger masses with those of the epsilon-regime for smaller
masses. From the partially quenched theory we also obtain the spectral density
of the Dirac operator, a smooth function from the microscopic region to the
bulk region of the p-regime.
