The present invention relates to a method and a system for simple implementation of requirements of telecommunications subscribers for services which can be provided by a communications network. According to the invention, the method includes abstracting and classifying the requirements into a corresponding number of classes, subdividing the individual classes into one or more subclasses, and uniquely associating a subclass with one or more technical functional units which can be coupled to one another in a corresponding manner. The system includes a first catalog of classes, in which each requirement can be associated with one class, and a second catalog of technical functional units, in which each class is associated with one or more specific technical functional units.