Abstract: A wave energy convertor (1) is provided comprising an elongate construction (2), typically a breakwater or harbour wall, located in a body of water having wave action associated with it with the waves moving generally in a dominant wave direction (10) and having a generally constant wavelength. A plurality of equally spaced chambers (20) extends along the length of the construction internally thereof with each chamber extending generally upwardly and having at or near its lowermost end (28) an opening (24) into the body of water. Each chamber communicates through a unidirectional valve (40, 42) respectively with each of a high pressure conduit (44) and a low pressure conduit (46) with the high pressure conduit feeding into an inlet to a turbine (56) and the low pressure conduit communicating with an outlet from the turbine. The length of the construction is approximately equal to an integral number of said generally constant wavelengths in the dominant wave direction.