Professor Marian Pasko obtained his D.SC. degree in 1994 from the Faculty of Electrical Engineering at the Silesian University of Technology, defending a thesis titled: "Selection of compensators to optimize the working conditions of one-phase and multi-phase voltage sources with periodical non-sinusoidal waveforms". The primary areas of his research are issues related to improving the power quality of electric systems operating in conditions of deformation of voltages and currents. His most important achievements include: optimization of working conditions of the non-sinusoidal periodic real voltage source by means of LC one-ports; application of LC one-ports in phase load symmetrization in n-phase systems with non-sinusoidal periodical waveforms; and design of LC compensator synthesis algorithm. Dr Grzegorz Benysek obtained his PhD degree in 1998 from the Electrical Engineering Department at the Technical University of Zielona Gora, defending a thesis titled: "An analysis of hybrid compensator systems for the filtration harmonic current in AC supply networks". On November 16th 2007 he obtained his D.SC. degree from the Faculty of Electrical Engineering, Computer Science and Telecommunications at the University of Zielona Gora, defending a thesis titled: "Improvement in the Quality of Delivery of Electrical Energy using Power Electronics Systems". From the beginning he was involved in two major research areas: 1. utilization of the FACTS in distributed electric power systems; 2. power electronics based arrangements for power quality improvement. His most important achievements include: design, development and experimental investigations of different types of the active power conditioners (filtration-compensation arrangements and FACTS, also on the base of multilevel-inverters); completion of theoretical and experimental studies of considered active power conditioners which allowed the most advantageous selection from the point of view of implementation; the universal control algorithm for active power conditioners assigned to both the symmetrical and non-symmetrical loads; and elaboration of probabilistic based methodology for active power conditioners power rating selection in distributed electric power systems. He also worked vigorously to inaugurate international cooperation with universities across Europe. The collaborations resulted in two research projects granted by the European Union, among others.