Detectors for sub-millimetre continuum astronomy

Sub-mm astronomy has seen an explosive growth in recent years. This has been driven by improvements in detector technology, and in particular the move from single pixel photometric instruments to ones containing arrays of hundreds and even thousands of pixels. Sub-mm detectors are different from those used in astronomy at most other wavelengths in that they are not produced commercially. Instead, research, development and construction is carried out in universities and government laboratories. We are also at an interesting point in that several competing detector technologies are under development and it is not yet clear which will be used in future instruments. I review current instruments as well as the issues facing us in developing the next generation of instruments, operating both on the ground and from space.