Increasingly, distributed nonlinear loads are influencing levels of power system harmonic distortion. As a result, the focus of harmonic control inevitably shifts from the local load to a network-wide level. Limitations and difficulties associated with passive filters have led to the proposal of active power-line conditioners as a method of network-wide harmonic control. This paper presents a control scheme which systematically brings network-wide harmonic levels within specified limits based solely on feedback information, thereby eliminating the requirement for a priori network impedance information. This proposed scheme offers substantial computational savings over full nonlinear optimization while achieving near-optimum results.