Roque de los Muchachos Observatory (La Palma) and Teide Observatory (Tenerife) are prime astronomical sites, as confirmed by more than 30 years of intensive site-testing campaigns. The IAC has long been aware of the importance of promoting initiatives for the characterization and protection of the Canarian Observatories. For this purpose, in the late ’80s a Sky Team was created to measure the atmospheric parameters relating to astronomical observations, to design and develop new instruments and techniques for astronomical site testing, and to improve and maintain a high level of instrumentation in site characterization. New instruments and techniques are welcomed by the Observatories.