This 1997 text contains maps showing the distribution of emission from atomic hydrogen, the principal interstellar medium in the Milky Way, as measured over a 5-year period using the 25-metre radio telescope of the Netherlands Foundation for Research in Astronomy. Displayed in several projections, each map corresponds to a particular velocity interval; separation by velocity roughly corresponds to separation by distance, or by energetics. The Leiden/Dwingeloo survey covers the entire sky above declination -30O, on a half-degree grid, over a velocity range of 1000 km/s at 1 km/s resolution. The limiting brightness temperature sensitivity is <0.07 K. A CD-ROM accompanies the Atlas, and contains the entire dataset of the Leiden/Dwingeloo survey in computer-readable form.