The Study Committee C4 (Power System Technical Performance) is responsible for advanced methods and tools for analysis related to power systems. Areas of attention include: Power Quality Performance: Continuity of end-to-end electric power supply and voltage waveform quality (magnitude, frequency, symmetry). Analysis covers emission assessments from disturbing installations, measurement and simulation methods, identification of quality indices, monitoring techniques, immunity of sensitive installations, and mitigation techniques taking into account a co-ordinated approach across all voltage levels. Electromagnetic Compatibility (EMC): High frequency disturbances on the end-to-end electricity supply and all disturbances (HF or LF) reaching equipment other than through the electricity supply. Studies include measurement and simulation methods. Health effects related to low frequency EMF are however excluded. Power System Dynamics: Development of advanced tools and new analytical techniques for assessment of power system dynamic/transient performance, security, design of controls and modelling of existing and new equipment, real time stability evaluation and control. Lightning: Analysis of lightning characteristics and interactions of lightning with electric power systems and equipment, including protection in MV and LV networks against lightning, and their standardisation. Insulation Co-ordination: Methods and tools for insulation co-ordination and electromagnetic transient analysis in electric power systems and equipment, contributing to optimisation of their cost and reliability. Babak Badrzadeh is currently the Managing Director of Etik Energy a consultancy business based in Melbourne, Australia. He has more than 20 years of multi-sector power industry experience including positions at AEMO, Vestas Aurecon, and Mott MacDonald. He has provided consultancy services to many national and international organisations ranging from system operators, network owners, plant owners and developers, policy makers, original equipment manufacturers, and research institutions. He has investigated a wide range of practical power system phenomena, ranging from DC to MHz, and more than 15 different types of generation and load technologies in different countries. His contributions to international organisations include successful completion of three CIGRE Technical Brochures as the Convener, a Special Reporter of SC C4 in 2022 Paris Session, an ongoing Associate Editor of IEEE Power and Energy Society (PES) Magazine, and a distinguished lecturer of IEEE PES. Babak is a Fellow of Engineers Australia, an adjunct Professor at Monash University, a recipient of Energy Systems Integration Group (ESIG) Excellence Award and the Convener of CIGRE Australia C4 Panel on Power System Technical Performance.  Zia Emin received his BSc in Electrical & Electronics Engineering from the Middle East Technical University, Ankara, Turkey and MSc and PhD degrees from The University of Manchester, Manchester, United Kingdom. He has worked as a power system engineer specializing in the planning and development of electric power networks, initially with National Grid and later with Parsons Brinckerhoff (later WSP) and PSC. Since 2023 he is working in Electric Power Research Institute (EPRI) as a technical executive. He has extensive knowledge in all aspects of power system modelling including steady-state, frequency and time domain modelling and substantial experience in harmonic performance specifications of power electronic interfaced devices (HVDC converter stations, FACTS, renewable generation connections etc). He has been active in many CIGRE (International Council on Large Electric Systems) working groups as member, task force leader and convenor within system technical performance area. He received the CIGRE Technical Committee Award in 2013 and the Distinguished Member award in 2014. From 2016 to 2022 he was the chairman of CIGRE SC C4 and its Strategic Advisory Group. In this role as CIGRE Study Committee Chairman he was responsible for the formation, operation, and deliverables of around 40 highly specialized technical working groups. He was also a member of the CIGRE Technical Council at international level and the past chair at national level (CIGRE-UK). Currently he is a member of the CIGRE Strategic Advisory Board. He is a Fellow of the Institute of Engineering and Technology (IET - UK), a Senior Member of IEEE, a Distinguished and Honorary Member of CIGRE, a European Engineer, and a Chartered Engineer in the United Kingdom.