In Section 19.1 we discuss the scope of database security and examine the types of threat that may affect computer systems in general. In Section 19.2 we consider the range of computer-based controls that are available as countermeasures to these threats. In Sections 19.3 and 19.4 we describe the security measures provided by Microsoft Office Access 2003 DBMS and Oracle9i DBMS. In Section 19.5 we identify the security measures associated with DBMSs and the Web. The examples used throughout this chapter are taken from the DreamHome case study described in Section 10.4 and Appendix A.