The objective of this proposal is the development of a full- field measuring technique for particle velocity and size based on particle image velocimetry methods. The resolution, accuracy and biases of the technique will be investigated. The approach will be illustrated for a transient spray. The main areas of application will be in two-phase turbulent and transient flows. A main contribution is the automation of particle size measurement, as an alternative to direct imaging. A key issue which has to be solved is the correlation between the velocity and particle size. If successful, the proposed technique will be a significant advancement for a combined full-field particle velocimetry and particle sizing measurement, with application to particles, droplets or bubbles of any shape. This is a complimentary method for the point measurements with phase Doppler velocimetry.