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This paper investigates longitudinal and transverse flux linear motor topologies for very high acceleration rate (3-4 g), and high speed (120 km/h), material transport systems which have significant technical and economic potential in flexible manufacturing environments. The general topology under consideration is a double-sided, short-moving-secondary/long-fixed-primary, linear induction motor (LIM). The transport system requirements place severe demands upon the machine topology. In addition to efficient thrust production, the linear machine must be capable of generating large unbalanced normal (i.e., lateral) forces in order to achieve electromagnetic (mechanically passive) steering of vehicles with both straight and curvilinear primaries. Air gap chording and short secondary effects are two additional design complications. Minimization of the primary leakage inductance is necessary not only to minimize inverter ralings but also to maximize the influence of the secondary state on the primary terminal properties for magnetic flux and position/velocity estimation. The orientation of the magnetic flux (i.e., longitudinal versus transverse) has a significant impact upon the above concerns and is thus a major analytical focus of this paper. A hybrid system topology consisting of a longitudinal-flux orientation within straight sections and a transverse-flux orientation within curvilinear sections appears to offer the best of both topologies. The intended contribution of this paper is a detailed comparison of LIM topologies leading to a better design selection for very high performance systems.