The western Hellenic subduction zone (western Hellenic Arc) has historically generated among the most devastating earthquakes and tsunamis in the entire Mediterranean region. Tectonically, the Hellenic subduction accommodates consumption of the Neotethys ocean lithosphere during the final stages of Africa-Eurasia continental collision. Widespread shortening of lithosphere occurs today over a distance of 400 km along the western coast of Greece accommodated by seismic slip along the megathrust interplate boundary, upper plate faults and the Cephalonia Transform Fault. Toroidal flow around the edges of the retreating slab has been suggested to account for tectonic processes in both southwest Anatolia (Turkey) and the western Peloponnese. We invite new geophysical (seismic, geodetic etc) and geological observations and analyses providing new insights on the Ionian Sea tectonics, subduction processes, lithosphere-mantle interactions and earthquake hazards in that area. We also invite contributions in response to the Ionia Sea M6.5 earthquake that occurred on November 17, 2015 in Lefkada, and subsequent mass movements, deformation, fault rupture, building damage and aftershocks.