The talk describes the world wide effort to detect gravitational waves from astrophysical sources by long baseline laser interferometry. Projects in Europe, the United States of America, Japan and Australia hope to be operating within the coming decade.

The talk includes:
– the concept of the detectors and prototypes,
– the noise limits to the sensitivity,
– a review of the known and posited astrophysical sources,
– some details of the LIGO (Laser Interferometer Gravitational-wave Observatory),
– the techniques to give confidence to a detection.