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Teleseismically located earthquakes in the New Hebrides Arc are unevenly distributed along the length of the subduction zone. Shallow seismicity near the plate boundary fits a static model of plate interaction along an interface with varying degrees of coupling between overriding and subducting plates. This interpretation is supported by striking differences in source radiation from earthquakes occurring in different parts of the plate boundary, and by systematic along-strike variations in forearc morphology. The irregular distribution of intermediate-depth seismicity can be considered from two opposing points of view: one assuming a continuous or relatively uniform subducted slab; the other invoking an irregular, possibly discontinuous slab. At the northern and southern ends of the Neiv Hebrides Arc, abrupt changes in the length of the inclined seismic zone coincide with structural and geophysical discontinuities in the subduction zone; a recent elongation of a previously shorter island arc northward and southward could explain many of these observations. In cross section, the intermediate-depth events define a spoon-shaped profile, with a nearly vertical plunge from 100 to 200 km depth and a gentler 60° dip below that. The disrupted morphology and seismicity of the central Neiv Hebrides Arc is also considered using both the uniform and non-uniform lithosphere models. Although the tectonic complexity at depth may imply disruption of the subducted lithosphere, the present subduction of the D’Entrecasteaux fracture zone plays a dominant role in the shallow deformation of this portion of the island arc.