A systematic theory is given for the output-sliding control (OSC)of linear time-invariant systems with concentrated parameters. It is shown that the output tracking error can be guaranteed to converge to zero with an exponential rate. The closed-loop eigenvalues in the sliding mode can be effectively assigned by the use of OSC. System robustness is achieved with respect to a larger class of disturbances and parameter variations than that by the use of conventional state-sliding control (SSC). Supporting techniques are given for the implementation of the theory. An illustrative example is studied to show the superiority of OSC over SSC.