Proceedings of the 133rd Symposium of the International Astronomical Union, held in Paris, France, June 1-5, 1987 I.A.U. Symposium No. 133, "Mapping the Sky: Past Heritage and Future Directions" was held at Paris on 1-5 June, 1987. The rationale for this meeting is to combine historical and modern aspects of mapping the sky; historical in that the meeting celebrates the initiation of the carte du Ciel at the Observatoire de Paris in 1887 and evaluates its impact on astrometry and astronomy in general. And modern in the sense that now in optical, radio and other wavelengths the sky is and needs to be charted in detail. The Symposium also commemorates the 150th anniversary of the first trigonometric parallax. The proposal for the meeting closely involved the sponsoring I.A.U. Commissions 24 and 41 and their respective officers. The Scientific Organizing Committee included the two current presidents of these commissions as co-chairmen (A.R. Upgren and J.A. Eddy, respectively) along with V. Abalakin. S. Debarbat, Ch. de Vegt, R.L. Duncombe, H.K. Eichhorn, M. Hoskin, J.A. Hughes, C. Jaschek, P.G. Kulikovsky, C.A. Murray and P.A. Wayman. The L.O.C. consisted of P. Charvin (chairman), S. Grillot, L. Garin and R. Weinstein; they were helped by M. Alibert (secretary), G. Rault, S. Seguier, J. Counil and S. Debarbat. Additional financial support was provided by the Division of History of Science, International Union for the History and Philosophy of Science.