Subduction of heterogeneities in the incoming plate such as active spreading ridges often leads to the formation of gaps in the downgoing slab. Such gaps or windows allow transfers between the subslab mantle and the mantle wedge, altering traditional subduction-zone mantle flow patterns and contributing to anomalous volcanism and changes in the tectonics and topography of the upper plate. The particular response in any given setting is varied, yielding a complex picture of how window/gap formation relates to their geologic signature at the surface. Here we invite submissions from a variety of disciplines - particularly tectonics, geomorphology, seismology, geochemistry, laboratory  and numerical geodynamic modeling in order to characterize the global distribution of slab window/gap features and investigate the relationship between induced mantle dynamics and shallow processes.