SEVENPAR is a tool for the calculation of highly exact transformation parameters for the Spatial Helmet and Molodensky Transformation, which make possible precise coordinate transformations from one reference system into another. The determined transformation parameters can be entered directly into suitable transformation software, e.g. TRANSDAT Coordinate Transformations, or into the calculation software of GPS receivers to do exact coordinate transformations. The seven or three transformation parameters are computed with a set of individual identical points. Those are points with known coordinates in both reference systems (geodetic datum). Cartesian coordinates, geographical coordinates or UTM coordinates with or without ellipsoidal height using the ellipsoid dimensions are suitable. Identical measuring points of higher order can be usually inquired or referred by the official institutions for measurement. The necessary ellipsoid half-axes and flattening\'s are available in the program for the selection from lists. The coordinates of the identical points are tested intensively on outliers and deviations by different statistic procedures. The quality of the computed parameters is documented by a residual matrix and by the computation of the middle, maximum and root mean square (RMS) deviations. The seven parameters of the Spatial Helmet Transformation are calculated in the three most usual standards Coordinate Frame Rotation, Position Vector Transformation and European Standard ISO 19111. The three parameters for Molodensky parameter sets are calculated using the Standard Molodensky Transformation. The program has user-selectable interfaces in English, Spanish, French, Portuguese and German language and comes with extensive bi-language online help. It can be run on most common networks and it is possible to use Terminal Services on WINDOWS Servers. The client installations are done automatically.