1. A method for offline programming a numerical controller-controlled (NC-controlled) manipulator which follows at least one real trajectory, possibly in a sensor-supported manner, with tool center point thereof in a real working mode, using an offline programming environment comprising an offline programming system and a user interface, the method comprising the steps of: storing a kinematic manipulator model and, possibly an environmental model in the offline programming environment; using the offline programming environment in a definition routine to define at least one virtual trajectory of the NC-controlled manipulator and a virtual tolerance zone assigned to said trajectory; and using the offline programming environment to implement a check routine to check the virtual tolerance zone, which is previously defined at least in part in terms of kinematic singularities of the NC-controlled manipulator, and if an occurrence of a singularity is determined prompting a singularity routine to be executed.