A rotary seal comprises a seal element comprising a disc-shaped body having a first axial side and an opposed second axial side. The seal element further comprises a radially inner central circular opening for receiving a rotary shaft, the opening having an inner periphery for sealing engagement with the shaft. A radially outer rim portion of the seal element comprises an axially facing annular sealing surface provided on the first axial side for sealing engagement in use with an opposed axially facing sealing surface of an adjacent first static housing and an axially facing pocket provided on the second axial side and having an axially facing surface for receiving, in use, an annular elastomeric biasing element. At least one drainage passage is formed through the outer rim portion from an inlet on the second axial side to an outlet on a radially outer portion of the rim portion.