An adapter assembly for selectively interconnecting a surgical loading unit that is configured to perform a function and a surgical device that is configured to actuate the loading unit, the loading unit including at least one axially translatable drive member and the surgical device including at least three rotatable drive shafts (118, 120, 122), the adapter assembly comprising: a housing configured and adapted for operative connection with the surgical device; an outer tube having a proximal end portion supported by the housing and a distal end portion configured and adapted for operative connection with the loading unit; a plurality of force/rotation transmitting/converting assemblies (240, 250, 260) disposed within the housing and the outer tube, wherein each of the plurality of force/rotation transmitting/converting assemblies includes: a proximal rotation receiving member (212, 214, 216) that is connectable to a respective one of the at least three rotatable drive shafts of the surgical device; and a distal force transmitting member (248, 252, 266), each of the distal force transmitting members being connected to each of the proximal rotation receiving members, respectively; wherein at least one distal force transmitting member (248, 252, 266) is connectable to the at least one axially translatable drive member of the loading unit, wherein a rotation of at least one of the proximal rotation receiving members is converted into an axial translation of the respective distal force transmitting member; wherein at least one of the plurality of force/rotation transmitting/converting assemblies converts and transmits a rotation of the respective one of the at least three rotatable drive shafts of the surgical device to an axial translation of the at least one axially translatable drive member of the loading unit; characterised by each of the proximal rotation receiving members being arranged in a common plane with one another. a housing configured and adapted for operative connection with the surgical device; an outer tube having a proximal end portion supported by the housing and a distal end portion configured and adapted for operative connection with the loading unit; a plurality of force/rotation transmitting/converting assemblies (240, 250, 260) disposed within the housing and the outer tube, wherein each of the plurality of force/rotation transmitting/converting assemblies includes: a proximal rotation receiving member (212, 214, 216) that is connectable to a respective one of the at least three rotatable drive shafts of the surgical device; and a distal force transmitting member (248, 252, 266), each of the distal force transmitting members being connected to each of the proximal rotation receiving members, respectively; a proximal rotation receiving member (212, 214, 216) that is connectable to a respective one of the at least three rotatable drive shafts of the surgical device; and a distal force transmitting member (248, 252, 266), each of the distal force transmitting members being connected to each of the proximal rotation receiving members, respectively; wherein at least one distal force transmitting member (248, 252, 266) is connectable to the at least one axially translatable drive member of the loading unit, wherein a rotation of at least one of the proximal rotation receiving members is converted into an axial translation of the respective distal force transmitting member; wherein at least one of the plurality of force/rotation transmitting/converting assemblies converts and transmits a rotation of the respective one of the at least three rotatable drive shafts of the surgical device to an axial translation of the at least one axially translatable drive member of the loading unit; characterised by each of the proximal rotation receiving members being arranged in a common plane with one another.