The rapidly expanding market for Spatial Data Mining systems and technologies is driven by pressure from the public sector, environmental agencies and industry to provide innovative solutions to a wide range of different problems. The main objective of the described spatial data mining platform is to provide an open, highly extensible, n-tier system architecture based on Java 2 Platform, Enterprise Edition (J2EE). The data mining functionality is distributed among (i) Java client application for visualization and workspace management, (ii) application server with Enterprise Java Bean (EJB) container for running data mining algorithms and workspace management, and (iii) spatial database for storing data and spatial query execution.