This video presents the experimental testing of a novel, intelligent damping system for civil engineering structures. The semi-active tuned liquid column Damper (S-TLCD) was developed and patented at the Chair of Structural Analysis and Dynamics. The video demonstrates the effect of the damper by two experiments. The first experiment shows the low damping effect caused by the parameter misalignment, which is usually the case for passive dampers. During the second experiment S-TLCD reaches a much higher damping efficiency through its adaptive parameter tuning character." This is part of the Open Educational Resources Initiative by the Faculty of Civil Engineering of the RWTH Aachen University.