Fusing of glass tubes is of particular interest for wide range of applications (e.g. solar receivers and chemical apparatus). The production of these rotation-symmetric connections is dominated by a flame-based heating and melting technology using gas burners. This conventional method has reached its limits in terms of many points of view. The most critical ones are water condensation, soot, low incoupling efficiencies of the flame energy and varying stress fields in the glass tubes which results from undefined temperature distributions of the flames during the fusing process. Furthermore, an energy-intensive downstream tempering process is necessary in order to relax the glasses and eliminate the stresses that were induced during the prior fusing process. This paper introduces the novel laser-based fusing technology of glass tubes. The used CO2-laser radiation has all the features to overcome the above-mentioned disadvantages of the present flame technology. Due to the used wavelength this method is applicable for all kinds of glass. The knowledge about the absorption behavior coupled with a closed loop controller led to a new fusing possibility. Furthermore, the control of the stress distribution becomes possible. The physical backgrounds, the experimental set-up as well as an overview of the fusing process will be shown. Finally, verified results will complete the paper for industrial users.