The lattice definition of a two-dimensional topological field theory (
TFT) is given generically, and the exact solution is obtained explicit
ly. In particular, the set of all lattice topological field theories i
s shown to be in one-to-one correspondence with the set of all associa
tive algebras R, and the physical Hilbert space is identified with the
center Z(R) of the associative algebra R. Perturbations of TFT's are
also considered in this approach, showing that the form of topological
perturbations is automatically determined, and that all TFT's are obt
ained from one TFT by such perturbations. Several examples are present
ed, including twisted N = 2 minimal topological matter and the case wh
ere R is a group ring.