1. Membrane phase was monitored using the membrane probe Laurdan. Excitation of the laurdan-doped T-cells was accomplished using two-photon excitation and scanning across the T-cell to develop a complete 3-dimensional cellular map of membrane phase information. 2. Cellular free Ca++ concentrations were monitored using the calicum dye fura 2 . Preliminary results on calcium standards have been performed with success. Future work includes 3-dimensional scanning of fura-containing T-cells and reconstruction of a 3D , free Ca++ concentration map of the cell.