The main limitations of string field theory arise because its present
formulation requires a background representing a classical solution, a
background defined by a strictly conformally invariant theory. Here we sketch a
construction for a gauge-invariant string field action around non-conformal
backgrounds. The construction makes no reference to any conformal theory. Its
two-dimensional field-theoretic aspect is based on a generalized BRST operator
satisfying a set of Weyl descent equations. Its geometric aspect uses a complex
of moduli spaces of two-dimensional Riemannian manifolds having ordinary
punctures, and organized by the number of special punctures which goes from
zero to infinity. In this complex there is a Batalin-Vilkovisky algebra that
includes naturally the operator which adds one special puncture. We obtain a
classical field equation that appears to relax the condition of conformal
invariance usually taken to define classical string backgrounds.Comment: 38 pages, 4 figures, phyzzx and BoxedEPS include