This session will focus on the structure, evolution and behaviour on different time scales of rifts and other zones of continental extension as revealed by recent tectonic, seismological and geophysical studies. How is deformation distributed on a normal fault network? How does a normal fault network evolve as deformation accumulates and possibly migrates? Are detachments always necessary? What are the mechanical processes that are active on different time scales? What is the role of rheology and how does it evolve in time and space? What are the consequences for seismic hazard (rooting depth of faults, earthquakes on large detachments, lateral connectivity of faults and maximum earthquake magnitude)? Presentations of multidisciplinary projects combining for example, seismology, structural geology and mechanical modelling will be particularly welcome.