Demands placed on spectrophotometric detectors for use in flow-injection systems are discussed. Based on this background, it is proposed that it is worthwhile investing in high-performance detectors and other hardware to make the best use of the advantages of flow-injection methods. A novel flow cell that utilizes optical fibres to transmit light through a capillary, from and to a photometric detector, was applied in experiments that demonstrated the difference between flow systems with sample and with reagent injection through the application of gradient techniques such as electronic dilution. It is show that it is possible to extend the dynamic range of flow-injection systems using gradient techniques, but not in the case of reagent injection.In another set of experiments, the small illuminated volume of the detector cell (< 1 μl) made it possible to measure directly the segmented stream of aqueous and organic phases in flow-injection extraction without phase separation.The monitoring of a pesticide served as a basis for comparison between classical flow-injection extraction and the novel extraction without phase separation. Although the detection limit is lower in the classical technique, extraction without phase separation has the advantage of allowing simultaneous monitoring of the aqueous and organic phases and eliminating the need for the failure-prone phase separation step. A simple sorting program is introduced as an alternative data analysis scheme for the measurement of peak widths and for the evaluation of data gained from flow-injection extraction without phase separation. It proved to be much faster and considerably simpler to use than previous routines.