Sometimes, at work, as a young researcher, I had observed, that the many approaches to a technical problem was a source of conflicts, even of internal competitions. But, I with many others have always seen and enjoyed the great diversity exemplified at the Institute. Diversity in the topical researches, in the scientists backgrounds, in the approaches to solve problems… This diversity factor was always there… It turns out that despite the different winds of changes – the inhouse client approach, the stage gate model – this great diversity in viewing, approaching problems and proposing solutions was a force, one that grew and matured. A force that is exemplified and transpires in current achievements. The compilation of the scientific texts presented here is a testimony of our achievements, finding its root in the past and shoning light on the future. This does not only celebrate an anniversary of the Institute but consolidates a vision, since technological innovation has become a pillar of Hydro-Québec’s strategy. IREQ, Hydro-Québec’s research institute, employs scientists and technologists with a large variety of backgrounds, and administrative and support personnel. These human resources team up to carry out studies covering an extended range of research topics concerned by generation, transmission and distribution of electricity.