text: The experimental setup to perform Raman spectroelectrochemistry consists of a light source, a spectrometer, a potentiostat, a spectroelectrochemical cell, a three-electrode system, radiation beam conducting devices, data collection and analysis devices. Nowadays, there are commercial instruments that integrate all these elements in a single instrument, significantly simplifying the performance of spectroelectrochemical experiments. 
  * Light source. It provides the monochromatic electromagnetic radiation that interacts with the sample during the electrochemical process. In Raman-SEC, the light source is usually a laser corresponding to the VIS or NIR regions, which commonly emits at 532, 633, 785 or 1064 nm,  although there is the possibility of using many other lasers, including UV-lasers.
  * Spectrometer. It records the scattered radiation and provides the Raman spectra of the molecules. In Raman-SEC, spectrometers are usually combined with confocal microscopes (micro-Raman) to remove the information out of the focus, obtaining an excellent spectral resolution. However, it is possible to work with low resolution Raman spectrometers obtaining very good results.
  * Potentiostat/Galvanostat. It is the electronic device that allows controlling the potential of the working electrode respect to the reference electrode, or controlling the current that passes respect to the auxiliary electrode. 
  * Three-electrode system. It contains a working electrode, a reference electrode and an auxiliary electrode. This system can be simplified by using screen-printed electrodes that include all three electrodes in a single holder. 
  * Spectroelectrochemical cell (SEC cell). It is the device that includes the three-electrode system and allows the simultaneous recording of the Raman spectra of the species and the electrochemical signal. It is the link between optical and electrochemical techniques. 
  * Devices for conducting the radiation beam: lenses, mirrors and/or optical fibres. The last ones conduct the electromagnetic radiation over long distances with hardly any losses. In addition, they simplify the optical configurations since they allow working with a small amount of solution; in this way, it is easier to conduct and collect the light in the nearness of the electrode.
  * Data collection and analysis devices. It consists of a computer to collect simultaneously the signals provided by the spectrometer and the electrochemical instrument. Using an appropriate software, the generated signals can be acquired, transformed, analyzed and interpreted.