A current measurement method comprising: measuring by way of a measurement arrangement a load drawn current signal in each of at least three conductors (L1, L2, L3) of a multi-phase electricity supply to provide a respective output signal; applying a reference input signal to the measurement arrangement wherein the output signal measured in respect of a conductor comprises a load output signal corresponding to the load drawn current signal in the conductor and a reference output signal corresponding to the reference input signal; the current measurement method characterised by: determining at least first and second transfer function ratios, the first transfer function ratio being determined in respect of a first pair of conductors and the second transfer function ratio being determined in respect of a second pair of conductors, the at least first and second transfer function ratios being determined in dependence on at least a part of each of output signals measured in respect of the at least three conductors and which lacks a reference output signal, each transfer function ratio being determined differently from the at least one other transfer function ratio in respect of at least one of real and imaginary parts in at least one frequency band and time window of the output signals; and making a determination in respect of at least one of: a measured load drawn current signal; and electrical power consumed by the at least one load, the determination being made in dependence on the at least first and second transfer function ratios, the reference input signal and at least a part of output signals measured in respect of the conductors and comprising reference output signals. measuring by way of a measurement arrangement a load drawn current signal in each of at least three conductors (L1, L2, L3) of a multi-phase electricity supply to provide a respective output signal; applying a reference input signal to the measurement arrangement wherein the output signal measured in respect of a conductor comprises a load output signal corresponding to the load drawn current signal in the conductor and a reference output signal corresponding to the reference input signal; the current measurement method characterised by: determining at least first and second transfer function ratios, the first transfer function ratio being determined in respect of a first pair of conductors and the second transfer function ratio being determined in respect of a second pair of conductors, the at least first and second transfer function ratios being determined in dependence on at least a part of each of output signals measured in respect of the at least three conductors and which lacks a reference output signal, each transfer function ratio being determined differently from the at least one other transfer function ratio in respect of at least one of real and imaginary parts in at least one frequency band and time window of the output signals; and making a determination in respect of at least one of: a measured load drawn current signal; and electrical power consumed by the at least one load, the determination being made in dependence on the at least first and second transfer function ratios, the reference input signal and at least a part of output signals measured in respect of the conductors and comprising reference output signals.