The presentation will start with a short review of the current state-of-the-art in research of tunnels under seismic loading, focussing on three main topics: field observations, physical modelling and analytical and numerical modelling. After setting the scene, some recent developments will be presented in each area. A novel monitoring system based on inertial measurement units installed in two tunnels in Chile will be presented where the data will be publicly available. A particular emphasis will be placed on plastic, post-cracking behaviour of the tunnel lining, as well as on the cumulative effect of multiple earthquakes on the soil-tunnel system behaviour. We will cover the development of the first post-cracking similitude laws for shaking table tests of tunnels, the effect of lining modelling, plastic behaviour of the ground and tunnel installation effects on the seismic behaviour. Finally the presentation will finish with the current gaps and future research needs.