A bleed valve having an inlet port and an outlet port. The bleed valve comprises mutually perpendicular radial, longitudinal and tangential axes arranged such that the outlet port is substantially in a plane defined by the longitudinal and tangential axes. The bleed valve also comprises at least one vane spanning the outlet port and having a first side and a second side, the first side being closer to the inlet port than the second side. The at least one vane defining a vector from its first to its second side that has non-zero radial, longitudinal and tangential components.