The principle ideas of the thin disk laser design will be illustrated and the advantages for operating different laser materials will be explained. The results for cw- and q-switched operation as well as for amplification of short (ns) and ultra-short (ps, fs) pulses demonstrate the potential of the thin disk laser design. The scaling laws for this laser design show that the power limit for cw-operation is far beyond 10 kW for one single disk and the energy limit is higher than 1 J from one disk in pulsed operation. Also the applicability of the thin disk laser concept to optically pumped semiconductor structures will be discussed. When pumping directly into the quantum wells the energy defect between pump- and laser photon can be smaller than 5% thus reducing the waste heat generated inside the semiconductor structure. First results demonstrate the potential of this new concept. Finally, a short overview of the industrial realization of the thin disk laser technology will be given.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.