  The existence of starspots on late-type giant stars in close binary systems,
that exhibit rapid rotation due to tidal locking, has been known for more than
five decades. Photometric monitoring spanning decades has allowed studying the
long-term magnetic activity in these stars revealing complicated activity
cycles. The development of observing and analysis techniques that has occurred
during the past two decades has also enabled us to study the detailed starspot
and magnetic field configurations on these active giants. In the recent years
magnetic fields have also been detected on slowly rotating giants and
supergiant stars. In this paper I review what is known of the surface magnetism
in the cool giant and supergiant stars.
