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The instantaneous structure of a spark ignition direct injection (SIDI) engine fuel spray and the effect of injection pressure on spray structure have been investigated using flow visualization and digital particle image velocimetry (DPIV). Fuel spray experiments have been performed within a non-motored research cylinder. Instantaneous images of the fuel spray are illuminated using single Nd:YAG laser pulses (3-5 ns pulse width) formed into a sheet and passed through the fuel spray. These images are captured using a digital camera connected to an image acquisition board and computer. Flow visualization experiments for a production DI fuel injector, four injection pressures (2.1, 3.4, 4.8, and 6.2 MPa), and a 2 ms injector pulse width illustrate the evolution and instantaneous flow structure of the dense transient spray as a function of injection pressure.