We present a new method for optimization: constrained global optimizat
ion (CGO). CGO iteratively uses a Glauber spin flip probability and th
e Metropolis algorithm. The spin flip probability allows changing only
the values of variables contributing excessively to the function to b
e minimized. We illustrate CGO with two problems-Thomson's problem of
finding the minimum-energy configuration of unit charges on a spherica
l surface, and a problem of assigning offices-for which CGO finds bett
er minima than other methods. We think CGO will apply to a wide class
of optimization problems.