Proceeding of the Joint International Symposium on Deformatuon Monitoring. 2-4 November, 2011. Hong Kong. China. Report. Presently the determination of the velocity field in the global reference frame is possible by using different space techniques and dense terrestrial networks from global to local and regional scales. Reliability of the velocity field determination is limited by a number of outliers which could be artefacts (related to the processing method, unmodelled or mismodelled effects) or real effects (snow coverage or freezing effects) as well as seasonal effects relevant to atmospheric or hydrologic influences on station's position. The analysis presented in this presentation is based on the 3-years of permanent GPS observations from ASG-EUPOS which is Polish Active Geodetic Network consisted of over 130 permanent sites established by the Polish Head Office of Geodesy and Cartography mainly for engineering, but also for scientific purposes. Two independent velocity fields were determined. One is the continuous model, second is related to the geological structures (discontinuities) of the territory that Poland lies. Analysis of residuals between these models are presented together with the interpretation by means of anthropogenical changes (mostly mining activities) and geophysical effects (local hydrology or seismicity).