An actuator system for a wearable orthotic device, the actuator system comprising: a transmission assembly ; an actuator assembly comprising a motor and a first portion of the transmission assembly that provides a speed reduction of a motor speed to an output speed; a driven joint member (16; 80) comprising an output portion of the transmission assembly and a connector component for connecting the driven joint member (16; 80) to a brace component of the orthotic device, wherein the connector component of the driven joint member (16; 80) includes a first attachment recess that is connectable to a first brace component of the orthotic device and a second attachment recess that is connectable to a second brace component of the orthotic device, whereby operation of the driven joint member (16; 80) rotates the first attachment recess relative to the second attachment recess to operate a joint of the orthotic device; flexible cabling that connects the driven joint member (16; 80) to the actuator assembly , wherein the driven joint member (16; 80) including the output portion of the transmission assembly is connected remotely from the actuator assembly by the flexible cabling (50; 51) that runs between the actuator assembly and the driven joint member (16; 80), to permit flexibility in positioning the driven joint member (16; 80) relative to the actuator assembly ; and a housing that houses the actuator assembly; wherein the actuator system is configured to be worn by a user and wherein the flexibility in positioning the driven joint member (16; 80) relative to the actuator assembly is such that knee varus and valgus angling and/or hip abduction/adduction in a frontal plane can be optimized for walking. a transmission assembly ; an actuator assembly comprising a motor and a first portion of the transmission assembly that provides a speed reduction of a motor speed to an output speed; a driven joint member (16; 80) comprising an output portion of the transmission assembly and a connector component for connecting the driven joint member (16; 80) to a brace component of the orthotic device, wherein the connector component of the driven joint member (16; 80) includes a first attachment recess that is connectable to a first brace component of the orthotic device and a second attachment recess that is connectable to a second brace component of the orthotic device, whereby operation of the driven joint member (16; 80) rotates the first attachment recess relative to the second attachment recess to operate a joint of the orthotic device; flexible cabling that connects the driven joint member (16; 80) to the actuator assembly , wherein the driven joint member (16; 80) including the output portion of the transmission assembly is connected remotely from the actuator assembly by the flexible cabling (50; 51) that runs between the actuator assembly and the driven joint member (16; 80), to permit flexibility in positioning the driven joint member (16; 80) relative to the actuator assembly ; and a housing that houses the actuator assembly; wherein the actuator system is configured to be worn by a user and wherein the flexibility in positioning the driven joint member (16; 80) relative to the actuator assembly is such that knee varus and valgus angling and/or hip abduction/adduction in a frontal plane can be optimized for walking. <EOS>