Today’s digital society is becoming extremely sensitive to disturbances in electric power supply. Outages and voltage dips occur frequently within the grid and on-site; harmonics are becoming omnipresent as well. The cost of poor power quality for doing business is still increasing. At present it is not economical to improve power quality at the supply level to meet the requirements of digital society. A wide range of solutions is available for integration into the electric installation: filters, neutral upsizing, dedicated circuits etc. Investment in mitigation however should be well-considered, and thus monitoring is indispensable. Characterizing power quality in terms of type of event, location, and frequency of occurrence is needed. Fortunately, metering devices are becoming affordable and applicable at the individual circuit level.