Volume 10 of Developments in Applied Spectroscopy presents a collection of twenty selected papers presented during the 10th National lleeting of the Society of Applied Spectroscopy held in St. Louis, Oct. 18-22, 1971. The 10th National Meeting was sponsored by the St. Louis Section, Society of Applied Spectroscopy in cooperation with Baltimore-Washington, Chicago, Cleveland, Cincinnati, Houston, Intermountain (Idaho Falls), Kansas City, New England, Niagra Frontier, Northern California, North Texas, Pittsburgh and Rocky Mountain (Denver) Sections of the Society and combined with the 22nd Mid-American Symposium. Both theoretical and applied principles were presented in sessions on emmision, atomic absorp­ tion, molecular, nuclear, mass, x-ray, flame, Massbauer, and magnetic resonance spectroscopy. In addition special symposia were held on on-line computers, spectra data processing and re­ trival, application of spectrographic techniques for the museum, in environmental control, in space, in biomedicinal, sampling, the analysis and characterization of electronic materials and gas chromatography. The members of the Program Committee, I. Adler, L. Beaver, J. E. Delmore Jr., J. Eichelberger, J. R. Ferraro, M. Fishman, C. L. Grant, X. W. Heitsch, W. M. Hickam, M. T. Jones, S. R. Koistyohann, J. Kopp, D. W. Larsen, F. Pogge, W. Ritchey, M. E. Salmon, R. K. Skogerboe, J. J. Spijkerman, P. Urone, C. Veillon, M. S. Wang, and J. S. Ziomek, and the other meeting committee members are to be commended for the excellent program. Thanks are also extended to the exhibitors for their part in making the meeting a success.