A method of protecting steel in concrete is disclosed. A voltage between two connections of a power supply is generated such that current can flow between a negative connection and a positive connection. In a first protection step, one of the connections of the power supply is electrically connected to the steel to be cathodically protected and a sacrificial anode is electrically connected in series with the other connection of the power supply such that the voltage generated by the power supply is added to the voltage generated between the sacrificial anode and the steel to produce a voltage greater than the voltage generated between the sacrificial anode and the steel alone. The power supply may be a cell or battery and may be combined with the sacrificial anode to form a single unit. In a second protection step that may follow the first protection step, the voltage generated by the power supply is no longer present and a current flows between the sacrificial anode and the steel to continue protecting and/or passivating the steel. This may be achieved by connecting the sacrificial anode directly to the steel.