A joint sleeve for assembling together a first blade section and a second blade section of a rotor blade assembly is disclosed. The joint sleeve may include an outer surface and an inner surface defining a cavity. The cavity may be configured to receive a joint end of the first blade section and a joint end of the second blade section. The joint sleeve may also include a plurality of openings defined between the outer and inner surfaces. The openings may be configured to receive fasteners for securing the joint ends of the first and second blade sections within the cavity. Additionally, a profile of the outer surface may be configured to generally correspond to an aerodynamic profile of the first and second blade sections such that a substantially continuous aerodynamic profile is defined between the first and second blade sections when the joint ends are inserted within the cavity.