The International Astronomical Union has encouraged the study of our galaxy through a series of symposia. This volume contains the proceedings of IAU Symposium No. 84 on the Large-Scale Characteristics of the Galaxy, held in College Park, Maryland, from June 12 to 17, 1978. Symposium No. 84 was jointly sponsored by IAU 2ommission 33, Structure and Dynamics of the Galactic System, and by Commission 34, Interstellar Matter and Planetary Nebulae. The Scientific Organizing Committee consisted of F. J. Kerr (chairman), B. J. Bok, W. B. Burton, J. Einasto, K. C. Freeman, P. O. Lindblad, D. Lynden-Bell, R. Sancisi, S. E. Strom, H. van Woerden, and R. Wielen. The topics and speakers were chosen in order to emphasize current observational material and theoretical results pertaining to various morphological aspects of our galaxy. In preparing the program particular care was taken to relate recent work on other galaxies to the situation in our own galaxy. The meetings were held in the Center for Adult Education on the campus of the University of Maryland. The Local Organizing Committee consisted of B. M .. Zuckerman (chairman), A. P. Henderson, P. D. Jackson, T. A. Matthews, B. F. Perry, V. C. Rubin, P. R. Schwartz, F. W. Stecker, J. D. Trasco, and G. Westerhout. Joan Ball ably assisted this committee. The National Science Foundation made a financial con­ tribution to the general support of the meeting. The National Radio Astronomy Observatory assisted with some of the participants' travel expenses.