  In this review we concentrate on the work of K. Alex M\"uller in connection
with his activities on oxide perovskites and ferroelectrics which were central
to his research career long before he successfully discovered the first high
temperature superconductor (HTSC) together with J. G. Bednorz in 1986. Not
accidentally, but taking his long experience in perovskite ferroelectrics into
account, the first HTSC was an oxide perovskite which had never been considered
before to be superconducting.
