Abstract: In a method and system for controlling the shape of an optical pulse, the two-dimensional shape of the phase front is controlled using a first control device and the shape of the phase front and the two-dimensional shape of the pulse front is controlled using a second control device. The combined effect on the phase front results in a desired overall phase front control and the second device provides the desired overall pulse front control. This enables the phase front control and pulse front control to be decoupled. Correcting for pulse lengthening of femtosecond laser pulses during focusing by a dispersive lens. The spatially varying phase (72) introduced by the lens can be corrected for by a spatial light modulator like (SLM) a liquid crystal modulator. The spatially varying arrival time at the focus (70) can be compensated for by a deformable mirror (DM). A controller with a feedback loop and pulse characterization in the focus can compensate for the errors introduced by any dispersive focusing means.