The present disclosure relates to an integrated boost modular multilevel converter, which has particular, but not sole, relevance to a converter for an inductive or capacitive (wireless) power transfer system. More particularly, the present invention according to an embodiment discloses a modular multilevel power converter (MMPC) comprising: at least one submodule stack having an output for connection to a load and an input for connection to an input power source, at least one inductive element provided between the input and the output, the at least one submodule stack including at least two submodules, each submodule comprising at least one capacitor and a plurality of controllable switches, and the submodules being operable to selectively transfer energy from the at least one inductive element to boost a voltage at the output relative to a voltage at the input.