This book presents new research related to femtosecond laser ablation, coherent control, electronic and thermal processes, colouring, nanoscale heat transfer, and corneal refractive surgery. With laser-pulse durations of one quadrillionth of a second, femtosecond lasers are poised to change the way research is done in a variety of disciplines in science, engineering and medicine. The ability to remove material with minimal collateral damage may be the most striking feature that has not been matched by any other material processing technologies. With the processing power carried by each pulse entering pettawatts (1015 W) in less than 100 femtoseconds, femtosecond lasers can remove virtually any type of material in a few picoseconds while confining the process zone to within tens of nanometers. The result is clean cuts, strong welds, and precision destruction of small targets such as cancer cells with no injury to surrounding materials.