In Germany the main interest of the early stages of work science was focussed on the area of work studies, especially on time-taking. Even today, work studies play an important role in efficient business management. In connection with forest work, which is characterized by changing working conditions and many influencing factors, work studies require especially high amounts of time and expenses. Immaculate input data are requirement for tenable interpretations of work study results, in which the method of transformation of the ''actual work times'' to the ''required work times'' is of major importance. What seems desirable in the interest of work science is the possibility of an unlimited information transfer of original data collections and results of data evaluations on a national and international level. So far, no satisfactory standardization has been achieved, neither regarding the terminology nor in work study methodology. Even within the German forest economy there are 2 rivalling systems for the presentation of work study results, the wide-spread REFA methodology which comprises many areas and a method which was specially developed by forestry work science in Germany. The differences and correspondences both in the structuring of the total process into work-cycle elements and in the classification of the work-cycle elements according to affinities regarding content into a sequence of stages of the work process types of time will be discussed. The abstraction of the individual performance capacities, included in the ''actual work times'', to an assumed reference performance - a problem which is dealt with in different ways on the level of sort of time - will be treated. At the same time, starting-points for overcoming the differences will be pointed out.