A PC-based interactive software package for low-level programmers is developed the for off-line programming of robots for welding, and is evaluated for are welding using a six-degree of freedom industrial robot. The package is also capable of simulating the process graphically. Weld trajectories are either determined by making use of user input three-dimensional weld seam drawings, or can be extracted from three-dimensional workpiece drawings. A module is developed for easy weld seam input, which also makes use of open-architecture libraries for classical weld geometries. The software package consists of modules for automatic selection of welding machine and robot programming parameters by making use of open-architecture libraries. The user can also override and input these parameters manually, whenever required.