Research into the PIV diagnostic method is aimed toward developing new algorithms for application of PIV to flows in which there are large spatial gradients in velocity. Limitations in existing analysis methods were identified and new approaches developed to track, measure and validate the displacements of individual seed particles and particle clusters in the flow field. An iterative, probability-based particle correspondence framework was then proposed that allowed improved discernment of displacement gradients within a field. Comparative results based on a set of vortical flow situations indicated that the new methodology could provide improved particle tracking for flows in which there are strong gradients.