High power CO2 Lasers are currently being used for various engineering applications such as welding, drilling, cutting, transformation hardening, surface alloying, cllading and glazing. It is the purpose of the presented paper to describe some aspects of the cutting application. The Laser as a cutting tool is described from both the system and the process points of view. The characteristics and performences of some typical Laser machining systems are described and a survey on the state of the art of Laser machining systems offered by various manufacturers is presented. Recent results of a study on metals cutting by a CO9 Laser are presented. The workpieces materials are Low Carbon Steel (AISI 1045), Stainless Steel (AISI 314L), Ti6A14V and Inconnel 718. The most significant tnetallurical transformations have observed in the Low Carbon Steel, thus, in comparison to the Stailess Steel, wherin the only observed damage phenomena are crakes and intergranular etching. In the H.A.Z. of the Titanium alloy the microstructure changes from a and IS phases to a martensitic phase (a') accompanied by the disappearance of the IS phase. In the H.A.Z. of the Inconnel an increase of the hardness and microcracks have been found although no microstructure change can be observed.