A number of organisms, including dolphins, bats and electric fish, possess sophisticated active sensory systems that use self-generated signals (for example, acoustic or electrical emissions) to probe the environment 1,2 . Studies of active sensing in social groups have typically focused on strategies for minimizing interference from conspecific emissions 2-4 . However, it is well known from engineering that multiple spatially distributed emitters and receivers can greatly enhance environmental sensing (for example, multistatic radar and sonar) 5-8 . Here we provide evidence from modelling, neural recordings and behavioural experiments that the African weakly electric fish Gnathonemus petersii utilizes the electrical pulses of conspecifics to extend its electrolocation range, discriminate objects and increase information transmission. These results provide evidence for a new, collective mode of active sensing in which individual perception is enhanced by the energy emissions of nearby group members.