Complex eliminations proceed with rearrangements. They’occur in most of the different branches of preparative organic chemistry. By relative notations of positions, they are ordered and named in a classifying way, independent from the respective reaction mechanism. Structural peculiarities of particular types are also included and distinguished. If only one or two groups or bonds migrate, the classifications are distinct and unequivocal. Nevertheless, in case of two migrating residues it is occasionally necessary to evaluate by labelling, which type the reaction belongs to. In the case of multiple migrations, it is necessary to divide the reaction into partial steps via (several) postulated or proved intermediates. The presented material shows synthetical potential and points out that most types can be realized according to different reaction mechanisms and under most different reaction conditions.