The paper describes a beam steering control system for a propagating laser beam, which is essential in free-space optical link. The tilt of the laser beam is measured with an indigenously developed Shack-Hartmann Wavefront Sensor (SHWFS) and dynamically compensated using a piezo-driven tip-tilt mirror. The system uses a commercial frame grabber and a CCD camera, which are less expensive. Spatial sampling of the beam with a 10 × 10 microlens array, Zernike Polynomial decomposition up to 4th order and real-time display of tilt-map are carried out. Tilt measurement to an accuracy of 2 pradians has been achieved. Experimental results of wavefront measurements using our SHWFS as well as tilt compensation are presented. © 2006 Taylor & Francis Group, LLC.