I have existing tables - I have following datatables : ActivityTable(Key ActivityId) - which lists the identifier for various activity ProcessTable (identified by ProcessId) - which lists down which activites(ActivityId) are to be carried out along with their order(StepNum). Some of the activities are marked constant with in a process, that is they will have same data, ir-respective of there run environment. RunTable(Key RunConfigurationId) - that identifies the project name and Process Id Then data for each activity is stored is stored in their individual tables Activity_A, Activity_B,Activity_C so on it uses a combination of RunConfigurationId,ProcessId and stepNum. For the activities which are constant we use a RunConfigurationId= -100. Can anybody help me out how I can map something like this in classes using inheritence regards