Title: Homogenization of space-time composites. Abstract: Space-time composites are composite materials whose microstructure exists not only in space but also in time. This novel notion was relatively recently put forward by Konstantine Lurie with a series of papers where he examined the propagation of electromagnetic waves through such a media. The mathematical difference between stationary and space-time composites is that the former is described by the elliptic system with rapidly varying coefficients, while the later - by the hyperbolic system of Maxwell's equations. In this talk we examine the homogenization theorem for Maxwell's system formulated by the formal similarity between the elliptic and hyperbolic systems. The present work done with my graduate student Hansun To attempts to justify the homogenization procedure for Maxwell's equations. We succeed in the case of a uniformly moving media. In the case of genuine space-time structures we encounter new difficulties not present in the elliptic case. For the uniformly moving media we apply Milton's W-transformation to automate the computation of the effective behavior of a moving laminate.