While devices based on micro effects are increasingly accepted in reaction engineering, there is still no breakthrough for separation applications like liquid-liquid extraction (LLE). This situation results from process design concepts which rely mostly on empirical work, involving high experimental effort and cost. Additionally, the limited throughput potential, mostly caused by complex fluid dynamics and difficult phase separation, is problematic. In this work the current state and potential of micro technology for LLE is discussed based on literature data. Afterwards, process simulations with a distributed plug flow model are used to access the specific advantages of this technology and to identify critical process parameters.