Professor Emanuel Riklis kindly asked me to open the Congress with a few words. Why me? Because I am probably the oldest participant in international photobiology meetings. In fact, my first one was the third in 1936, at Wiesbaden (Germany) 52 years ago, almost two generations, a long time is it not? At that time, the meeting was called “ Congrès International de la Lumière” (in French). The main topics were focused on the therapy of rickets, bone and skin tuberculosis, and of dermatosis, by ultraviolet rays, either natural from the sun (heliotherapy) or artificial from sources whose champion was the medium pressure mercury vapour lamp.