A report on recent progress of the National Textile Center's dye applications research group (DARG) in real time monitoring, modeling, and control of batch dyeing processes describes the modification of the flow injection analysis (FIA) system to enable injection of a small volume of dyebath into a high performance liquid chromatograph of dyebath into a high performance liquid chromatograph (HPLC) and the use of the FIA/HPLC system to analyze four different procedures for exhaust dyeing cotton fibers with reactive dyes. Preliminary data are reported for isothermal dyeings at different temperatures. Researchers are developing a spectrophotometric method for monitoring exhaustion of vat dyes that they will integrate into the FIA system for monitoring indigo in a dye range. Calibration models developed from indigo powder and indigo paste under a nitrogen atmosphere suggested substantial differences in dye purity. Researchers developed a neural network shade matching program that predicts dye concentrations more accurately than conventional linear models. Closed loop control of acid dyeing is reported. Researchers modified the DARG dyebath monitoring system to permit computerized controlled dosing of acid and base for pH control and measurement of individual dye concentrations and total sorption of each dye. 8 refs.