This application requests support for a session-in-depth (SID) on Cellular Aging at the world Congress on cell and Tissue Culture to be held in Washington D.C., June 20-25, 1992. The Congress, sponsored primarily by the Tissue Culture Association, will include participation by the European scientific community through the European Tissue Culture Association and the European Society for Animal Cell Technology. The SID will be co-convened by Drs. James R. Smith, U.S.A. and Sydney Shall, U.K. and will comprise a total of six speakers, including the conveners.