A prosthetic or orthotic system (100) including a magnetorheological (MR)damper. The MR damper may be configured to operate in shear mode. In oneembodiment, the MR damper includes a rotary MR damper. A controller isconfigured to operate the damper. A mobile computing device (320) may beadapted to intermittently communicate configuration parameters to thecontroller. A method of configuring a prosthetic or orthotic system is alsodisclosed.