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Three atomic spectroscopic databases of the U.S. National Institute of Standards and Technology are reviewed. First, our principal spectroscopic database, the Atomic Spectra Database (ASD), is discussed, which will soon be put on the internet in a new, entirely redesigned and expanded version 3.0. This new edition will include several additional critical compilations that were recently completed at NIST. Furthermore, two new smaller specialized databases will be reviewed, — a handbook of basic atomic spectroscopic data and a tabulation of data for soft x‐ray lines, tailored to the needs of x‐ray space observatories. Finally, an overview of our plans for new critical data compilations during the next two‐to‐three years will be presented.

A critical review and tabulation of the available experimental data on Stark widths and shifts for spectral lines non‐hydrogenic neutral atoms and positive ions has been carried out. The review covers the period from 1983 through the end of 1988 and represents a continuation of earlier critical reviews through the year 1982.

The status of experimental studies of the plasma broadening and shifts of non-hydrogenic neutral atom and positive ion spectral lines is reviewed, and the results of comparisons with theory are discussed. Advances in the experimental techniques and diagnostic procedures are also reviewed.

A summary of the contents and features of the new NIST Atomic Spectra Database is presented. All material in this large database has been obtained from critical data assessments done over the last 30 years. Only reference data, i.e., data fulfilling certain quality requirements, are included. For each spectral line and energy level, one numerical value—the “best” available value—is tabulated.

The National Institute of Standards and Technology (NIST) operates three data centers on atomic spectroscopy. These centers compile three principal quantities characterizing spectral lines: (1) Wavelengths and Energy Levels, (2) Atomic Transition Probabilities, and (3) Line Shape and Shift parameters. (AIP)