The unique computational framework developed by Lapusta and collaborators have provided transformative insights into the nature of earthquake processes and fault slip across scales. The model can predict the seismic (fast) and aseismic (slow) behaviour. She used this model to simulate various fault behaviours, including earthquake nucleation, post-seismic slip and inter-seismic deformation. Using a single model to simulate all fault behaviours made it possible for Lapusta et al. to demonstrate that during an earthquake the supposedly stable zones behave differently when penetrated by earthquake ruptures, and can in fact contribute to the generation of massive earthquakes through dynamic weakening. Her model could qualitatively reproduce the 2011 Tōhoku earthquake. uncovering the critical role of small scale frictional and hydromechanical processes and pointing to complex feedback interactions between fault slip, friction, and heterogeneous hydraulic properties that may qualitatively and quantitatively alter fault response from what may be inferred from small scale experiments Lapusta's work on small repeating earthquakes, interaction of seismic and aseismic slip in complex fault structures, and dynamic weakening that may potentially control the final size of an earthquake following its nucleation, has demonstrated the importance of rigorous mechanics-based modelling of earthquake processes, and how this may potentially be very informative to seismic hazard calculations particularly when data is scarce as it is the case for large earthquakes. For example, Lapusta studied the large areas of aseismic creep after the 2007 Peru earthquake, which can act to lower the seismic hazard in a particular region. Her computational work also includes using probabilistic inversion tools to understand tsunamis generated in during subduction zone earthquakes in deep-ocean trenches in Japan and Chile.