Staring at a level suitable for physicists with little specialist knowledege, this collection of papers presented at the 52nd Scottish University Summer School in Physics provides insight into the current developments and advances in lasers and their applications. The text starts with tutorial reviews of the underpinning science of diode pumped lasers, optical parametric oscillators and ultrafast pulse generation. It moves on through the more specialized areas of waveguide lasers, ultrafast parametric amplification, visible solid-state lasers, materials and diode pumps. The final sections are on the applications of these sources to medicine, remote sensing and ranging, material processing, and the widening set of applications for ultrashort pulses.