Abstract
It is now 20 years since Joseph Weber at the University of Maryland reported the detection of signals which he interpreted as gravitational waves of satrophysical origin Since then there have been no other reports of the direct detection of gravitationalwave signals although considerable progress has been made in experimental technique. Now, however, researchers in a number of countries believe it is possible to start building detectors sensitive enough, not only to detect gravitational radiation, but also to open up a new field in observational astronomy.