Viruses shape the growth and behaviour of their hosts, with effects that cascade to the ecosystem scale. The Mason-Jones Junior Group investigates the viral frontiers of soil ecology to understand how bacteriophages influence soil bacterial communities and regulate biogeochemical processes, including the cycling of carbon and plant nutrients. Our work experimentally dissects interactions between phages, hosts and other soil organisms using culture-dependent manipulations and culture-independent molecular techniques. We also aim to understand how phages deal with the unique challenges of the soil habitat. Experimental skills within the group are enhanced by collaboration with modellers, agronomists, and bioinformaticians across the Netherlands and internationally.