In this paper we describe a classifying theory for families of simplicial topological groups. If B is a topological space and G is a simplicial topological group, then we can consider the non-abelian cohomology H(B, G) of B with coefficients in G. If G is a topological group, thought of as a constant simplicial group, then the set H(B, G) is the usual set of isomorphism classes of principal G-bundles, or Gtorsors, on B. For more general simplicial groups G, the set H(B, G) parametrizes the set of equivalence classes of higher G-torsors. In this paper we consider a more general setting where G is replaced by a simplicial group in the category of spaces over B. The main result of the paper is that under suitable conditions on B and G there is an isomorphism between H(B, G) and the set of isomorphism classes of parametrized principal bundles on B, with structure group given by the fiberwise geometric realization of G.