The traditional approach to measuring segregation is based upon descriptive, non-model-based indices. A recently proposed alternative is multilevel modeling. The authors further develop the argument for a multilevel modeling approach by first describing and expanding upon its notable advantages, which include an ability to model segregation at a number of scales simultaneously. The authors then propose a major extension to this approach by introducing a simple simulation method that allows traditional descriptive indices to be reformulated within a modeling framework. The multilevel approach and the simulation method are illustrated with an application that models recent social segregation among schools in London, UK. (Contains 4 figures, 4 tables, and 4 notes.)