The aim of this paper is to give more details about the equipment used for isotachophoretic analysis. More accurate values, quantitatively as well as qualitatively, can be obtained by thermostating the system where the thermal detector is mounted. Mobilities of the different ion species are also strongly influenced by shifts in temperature. Therefore an electric diagram is given for an aluminum thermostat in which the capillary is mounted. A secondary effect, but also an important one, is that shorter times for analysis can be obtained because higher currents can be used by the increased heat transfer. Some electric diagrams are given for differentiating electronically, which makes balancing of thermocouples1,2unnecessary. Detailed designs are given for injection blocs and electrode compartments.