A method and apparatus for logical channel prioritization at a user equipment in a multiple uplink carrier system, the method receiving a set of logical channel priorities at the user equipment, the logical channel priorities being assigned on a per carrier basis; and applying the set of logical channel priorities to each logical channel for carrier selection. Further a method and apparatus for constructing an uplink medium access control protocol data unit at a user equipment in a multiple uplink carrier system, the method sorting possible logical channel and carrier pairings based on logical channel priorities; utilizing a prioritized bit rate process to allocate logical channel traffic in an order determined by the sorting; and performing a remaining resources process to allocate logical channel traffic based on a priority order.