The ISOPHOT Serendipity Survey fills the otherwise unused slew time be
tween ISO's fine pointings with measurements in an unexplored waveleng
th regime near 200 mu m. First results of the Serendipity Survey demon
strate its capabilities in the detection of extragalactic point source
s as well as in investigations of the galactic infrared cirrus. With t
he detection limit for point sources of similar to 1 Jy more than 3000
galaxies will be observed.