A gridded‐niobium target was constructed for the improvement of routine [18F]‐fluorine production from18O‐enriched water on a CTI RDS 112 cyclotron. Niobium was chosen for its inertness and excellent thermal properties. The target volume consists of a 400&mgr;L (active volume) niobium chamber mounted with a single entrance foil supported against an array of 3mm hexagonal holes with 0.25mm aluminum septa, machined by EDM. The target operates at high beam currents and elevated pressures and temperatures with significant reductions in maintenance intervals. Several diagnostic tools such as autoradiography, activation, and neutron logging optimize the performance and yield of the target. Entrance foils including Havar and Nb are used to assess the [18F] chemical compatibility, with FDG synthesis as the test reaction. The gridded, single‐foiled niobium target chamber appears to be an improvement compared to a standard double‐foiled helium cooled water target used with RDS cyclotrons. © 2003 American Institute of Physics