Abstract: Footwear assembly comprising a foot bed in an interior area defined by an upper and positioned atop a sole assembly, wherein the foot bed has a plurality of air holes through the forefoot and/or arch portions, and has air channels connected to the air holes. A compressible convex pump in the foot bed's heel portion faces the sole assembly and is movable between expanded and compressed positions. In the expanded position, the pump supports a portion of the heel portion apart from the sole assembly to define an air chamber coupled to the air channels. Movement of the pump member from the expanded position to the compressed position causes the air chamber to collapse and forces air from the air chamber through the air channels and upwardly through the air holes into the interior area of the upper, wherein the pump member is biased toward the expanded position.