ESDU 85032 provides procedures for the design and performance prediction of ejectors and jet pumps where both the primary and secondary streams are liquid. The first procedure obtains an optimum design for a required duty, and the second predicts performance of an existing ejector so as to study the effect of minor changes. The methods are based on one-dimensional flow theory, supplemented by empirical correlations for the losses within the nozzles and mixing duct, and the equations are detailed. Extensive design charts are included, and flowcharts guide the user through the simple step-by-step procedures which are illustrated by three detailed practical worked examples. Guidance is provided on the use of annular- or multi-nozzle arrangements, various mechanical aspects, and on the performance prediction of ejectors for gas flow, and on the avoidance of cavitation. See ESDU 93022 for a Fortran program of the calculation methods.