We have used the space based geodetic techniques of Satellite Laser Ranging (SLR) and Very Long Baseline Interferometry (VLBI) to study strain along subduction and transform plate boundaries and have interpreted the results using a simple elastic dislocation model. Six stations located behind island arcs were analyzed as representative of subduction zones while 13 sites located on either side of the San Andreas fault were used for the transcurrent zones. The length deformation scale was then calculated for both tectonic margins by fitting the relative strain to an exponentially decreasing function of distance from the plate boundary. Results show that space-based data for the transcurrent boundary along the San Andreas fault help to define better the deformation length scale in the area while fitting nicely the elastic half-spaced earth model. For subduction type boundaries the analysis indicates that their is no single scale length which uniquely describes the deformation. This is mainly due to the difference in subduction characteristics for the different areas, and the use of an elastic stress model then helps us understand some of these differences. ¿ American Geophysical Union 1993