The synthesis of a design procedure for a new type of liquid-liquid extraction column using present design knowledge is described. The emphasis is on engineering designability, simplicity of construction, and reliability of design, all of which are of great importance to industrial designers, rather than on smallest size or lowest cost. The results of calculations of performance are compared with published data for other types of column and they show that superior performance is possible. More work is required on the estimation of drop size formed at plate perforations as a function of stirring speed and on the velocity field of the continuous phase but first estimates are easily made. It appears justifiable to proceed with construction of a prototype to establish if the calculations are reliable.