I present a summary of recent work where we describe the time-evolution of a region of disoriented chiral condensate via Langevin field equations for the linear sigma model. We analyze the model in equilibrium, paying attention to subtracting ultraviolet divergent classical terms and replacing them by their finite quantum counterparts. We use results from lattice gauge theory and chiral perturbation theory to fix nonuniversal constants. The result is a ultraviolet cutoff independent theory that reproduces quantitatively the expected equilibrium behavior of pion and sigma quantum fields. We also estimate the temperature dependent viscosity, which controls the dynamical timescale in the Langevin equation, so that the near equilibrium dynamical response agrees with theoretical expectations.