During 1988–1990 Commission 7 has sponsored or co-sponsored several IAU conferences: Colloquium No. 109 “Application of Computer Technology to Dynamical Astronomy” (Gaithersburg, July 1988), Symposium No. 141 “Inertial Coordinate System on the Sky” (Pulkovo, October 1989), Colloquium No. 127 “Reference Frames” (Virginia Beach, October 1990), Colloquium No. 132 “Instability, Chaos and Predictability in Celestial Mechanics and Stellar Systems” (Delhi, October 1990). The colloquium No. 118 “Dynamics of Small Bodies in the Solar System” which was to be held in Nanjing in June 1989 had unfortunately to be postponed then cancelled. Other meetings of interest to the members of Commission 7 were the 2nd Alexander von Humbolt Colloquium on “Long Term Evolution of Planetary Systems” (Ramsau, March 1988), the Colloquium “Asteroids, Comets, Meteors III” (Uppsala, June 1989), the colloquium “Mécanique Céleste et Systèmes Hamiltoniens” (Luminy, May 1990) and the NATO Advanced Study Institute on “Predictability, Stability and Chaos in N-Body Dynamical Systems” (Cortina d’Ampezzo, August 1990).