The worldwide market for relational database management systems (RDBMS) grew by 11.6% to $14.9 bln in 2004, according to IDC. Although these numbers suggest a robust recovery for a market that has struggled over the past several years, IDC cautions that the picture is not as rosy as it seems. When currency exchange rates and downward pricing pressures are taken into consideration, the strength of the recovery is less clear. There were no changes among the top 5 RDBMS vendors from 2003 to 2004, with Oracle capturing top honors with 41.3% of the worldwide market. Oracle was followed by IBM and Microsoft with 30.6% and 13.4% market share, respectively. Rounding out the top 5 were Sybase and NCR Teradata, each with 3.1% market share. Microsoft experienced the strongest year-over-year growth on percentage basis and Oracle the strongest growth on a whole dollar basis in 2004, while IBM and Sybase both grew slower than the overall market. However, all five top vendors grew their database business in 2004. Moving into 2005, IDC expects the middle market to become the battleground for RDBMS dominance as Oracle and IBM move aggressively into the market while Microsoft, which currently dominates the middle market, prepares for the release of SQL Server 2005. Meanwhile, all the leading vendors will be working hard to head off any potential threats from open source RDBMS vendors.