Among other techniques for in situ and operando experimentation, Spectroscopic Ellipsometry (SE) can particularly be promoted as an analytical tool to diagnose solid-liquid interfaces. Besides other pionneer groups, our former heads Profs. J.M. Lecuire & R. Kleim initiated investigations dedicated to in situ electrode processes in liquid medium leading to the complete description of the evolution of an electrochemical interface through in situ, simultaneously and synchronized records of coulometric, optical and gravimetric data. The resulting setup is a home-made real-time spectroscopic ellipsometer with rotating compensator, operating  in the visible spectral range (at an acquisition rate of 25 ms), with simultaneous electrochemical measurements (30 ms), and optionally in surplus combinable EQCM measurement (160 ms). Last instrumental upgrades concerned  the elimination of systematic ellipsometer errors and the use of a supercontinuum white laser as source. To illustrate the opportunity of the proposed coupling for possible new incomers, three recent applications will be briefly exposed.