The aim of this work is to improve the concentration detection limits of commercial CE instrumentation using only a few cheap pieces of plastic. One of the greatest strengths of CE is its versatility and flexibility while the concentration detection limits are one of the most significant limitations of this technique. Sample stacking techniques were developed in order to overcome these limitations. However, even stacking methods face a limitation. The maximum sample volume available for injection is ca 1.5 mL when the commercial Agilent or Beckman instruments are used. It has been well documented that only a small proportion of the analyte ions present in the sample volume is elektrokinetically injected [1]. This limits the maximum amount of analyte ions that can be preconcentrated. A possible solution is to inject from a continuous sample stream. Here a continuous flow interface is presented which connects flow injection with the capillary electrophoresis components using a simple Tee connector. The effects of stacking by field enhanced sample injection (FESI) in combination with sweeping when using this continuous flow interface on the sensitivity enhancement were investigated. This work shows that with the same injection volume and time, the peak area (corrected by migration time) produced from the flowing sample interface is significantly larger than injection from a static vial. This demonstrates the potential of this interface for trace analysis. The ultimate goal is to rapidly flush high volumes of sample through the interface in a short time to concentrate analytes present at ng/L levels using an appropriate stacking technique. This approach would ultimately allow to further push the concentration detection limits of a broad range of existing techniques in CE.