Surveys, surveys, and yet more surveys! During the last decade we have all witnessed a flourishing of imaging and spectroscopic surveys, of different sizes and over different areas of the sky. Although initially set-up for specific scientific goals, they should all share a multi-purpose flavour that can boost their impact and their exploitation by the scientific community. There are, however, fields that need more dedicated observing strategies, coordination and possibly data infrastructure in order to exploit fully these huge datasets. Time-domain astronomy is one of them. In the following, I will review the very recent developments in spectroscopic surveys, and I will report on what ESO has been involved in and has committed itself to do.