Because of the overlapping interest of ASTM Committees E12 on Appearance of Materials and E18 on Sensory Evaluation of Materials and Products in vision and appearance, they have maintained liaison for many years, and joint sponsorship of this symposium was very appropriate. For Committee E12 the symposium effort represented an extension beyond instrumental measurements, which had received most of their attention. For Committee E18 it was a follow-up to ASTM Special Technical Publication 433, "Basic Principles of Sensory Evaluation" (1968), which included a chapter on vision and general chapters applying to all the senses. W. H. Danker, who was Chairman of Subcommittee E18.02 during the early planning in 1970 and 1971, was largely responsible for the initial proposal for a joint effort of the two committees and the later proposal that this effort take the form of a symposium. W. J. Kiernan, who was Chairman of Committee E12 in 1970, gave enthusiastic support to the proposed project and contributed many valuable suggestions for getting it underway.