Segregation, or un-mixing, of particles is a continued source of industrial frustration and can be a costly problem for industries ranging from pharmaceuticals to ceramics to agriculture. Particles that differ in almost any mechanical property-size, density, shape, etc.-have been shown to segregate even when the material itself is otherwise identical. Thus, distributions of mechanical properties can lead to performance issues when processing even "uniform" materials. While the majority of early studies of segregation focused on identifying mechanisms and kinetics of segregation processes. this foundational work has allowed a number of recent studies to aim at minimizing the extent of segregation in several industrially-relevant model systems. In this article, we highlight recent advances in controlling segregation and comment on future avenues of attack. (C) 2009 Elsevier B.V. All rights reserved.