  We study d=2, N=(2,2) non-linear sigma-models in (2,2) superspace. By
analyzing the most general constraints on a superfield, we show that through an
appropriate choice of coordinates, there are no other superfields than chiral,
twisted chiral and semi-chiral ones. We study the resulting sigma-models and we
speculate on the possibility that all (2,2) non-linear sigma-models can be
described using these fields. We apply the results to two examples: the SU(2) x
U(1) and the SU(2) x SU(2) WZW model. Pending upon the choice of complex
structures, the former can be described in terms of either one semi-chiral
multiplet or a chiral and a twisted chiral multiplet. The latter is formulated
in terms of one semi-chiral and one twisted chiral multiplet. For both cases we
obtain the potential explicitely.
