The field of atomization and sprays represents one of the most challenging areas of fluid mechanics. A full range of physical mechanisms are involved including liquid breakup, spray formation, and droplet interaction with a turbulent two phase flow with heat transfer and evaporation. Despite the incredible rise in computing power and innovations in computational fluid dynamics, reliably predicting spray formation, droplet dynamics, and spray interaction with turbulence remains elusive and problematic. Tracking individual droplet behavior is still beyond present day computing power. Detailed reliable experimentation is required if we are to gain the information needed to fully understand the fluid dynamics mechanisms involved and guide modeling efforts. Driven by these requirements, instrumentation innovation and development continues to progress by exploiting the rapid evolution of PC's, lasers, digital cameras and supporting electronics.