Title:               Every homotopy theory of simplicial algebras 
		     admits a proper model

Author:              Charles Rezk

AMS Classification:  Primary 18G55; Secondary 18C10, 55U35

Date:                March 10, 2000

Address:             Institute for Advanced Study 
                     Princeton, NJ 08540}
                     rezk@math.nwu.edu

Abstract:

We show that any closed model category of simplicial algebras over an
algebraic theory is Quillen equivalent to a proper closed model
category.  By ``simplicial algebra'' we mean any category of algebras
over a simplicial algebraic theory, which is allowed to be
multi-sorted.  The results have applications to the construction of
localization model category structures.