Abstract: A diode-pumped solid state laser system and a method of diode-pumping a solid state laser in which the emitter beamlets in the diode bar are directed at a beam transformation optical element which includes a continuous twisted surface to produce a uniform and symmetrised beam in the fast field which is then focused to match an input pump area of the gain medium of the solid state laser. Embodiments to square and rectangular flat-top intensity distributions are described using a Fourier lens and a set of cylindrical orthogonal lenses.