The question "Are we alone?" is perhaps the most fundamental that affects mankind (after that of the origin of the Universe). How can we address the search for life in our Solar System? Mars, the icy ocean satellites of Saturn and Jupiter such as Enceladus and Europa are in the focus of the planetary research topic to search for life outside the terrestrial biosphere. While it is more likely to find remnants of life (fossils of extinct life) on Mars because of its past short time window of the surface habitability, it is probably more likely to find traces of extant life on the icy moons and ocean worlds of the gas giants Jupiter and Saturn. Nevertheless, even on Mars there could still be a chance to find extant life in niches near to the surface.
Different approaches for the detection of traces of life in the form of biosignatures including pre-biotic molecules will be presented. The presentation will show in detail which infrastructure is needed for this enterprise from a scientific point of view and will give examples of future mission concepts to investigate the presence of life on other planets and moons. Finally suggestions will be provided on methods, techniques, operations and strategies for preparation and realization of future life detection missions.