  Decoherence and dissipation in quantum systems has been studied extensively
in the context of Quantum Brownian Motion. Effective decoherence in coarse
grained quantum systems has been a central issue in recent efforts by Zurek and
by Hartle and Gell-Mann to address the Quantum Measurement Problem. Although
these models can yield very general classical phenomenology, they are incapable
of reproducing relevant characteristics expected of a local environment on a
quantum system, such as the characteristic dependence of decoherence on
environment spatial correlations. I discuss the characteristics of Quantum
  Brownian Motion in a local environment by examining aspects of first
principle calculations and by the construction of phenomenological models.
  Effective quantum Langevin equations and master equations are presented in a
variety of representations. Comparisons are made with standard results such as
the Caldeira-Leggett master equation.
