The Front-end Engine (FEE) is responsible for coordinating the components involved in user interaction at the Front-end layer during planning and mining phases of Intension Mining[1]. It accepts all the user input and displays the messages to the user. Besides coordinating the various components present in the layer, FEE plays a significant role during compilation. It provides communication facilities, which are used by the Knowledge Discovery Schema Compiler for connecting to the destination DBMS. ODBC is very important at this level. Since FEE does all the 'talking' with the lower layer, installation of the user-defined functions in the library is performed by FEE on behalf of the compiler. At the mining stage, when the mining process communicates the results, FEE receives the output of the mining algorithm and invokes the appropriate presentation/visualization tool so that the knowledge can be presented to the user in the desired form. It also manages the library of presentation/visualization tools present in the Front-end layer. In order to perform all these functions FEE maintains a database required for its own operations and provides services to facilitate it's maintenance. Book-keeping information about all the schema entries, contents of the libraries etc. forms the database of FEE. Figure 4.1 shows an example set of services available with the FEE along with their users.