The lecture summarizes data on the structural and pharmacological properties of KCNQ channels, in particular KCNQ2-5, associated primarily with the nervous system. The KCNQ channels are known to play a crucial role in the control of neuronal excitability. Two classes of drugs altering KCNQ channel activity and therefore producing considerable changes in neuronal excitability are described. These are KCNQ/M channel blocking agents (linopirdine, TEA) and KCNQ channel enhancers (retigabine).