This session is a critical review of the technological field called IR Optical Design and Fabrication. When Warren Smith called me and asked for a paper that would look into the future, looking for trends, I pointed out that everyone here knew much more about IR optics than I—the list of papers and speakers attests to that! The years spent in the field of IR technology since I first began at The University of Michigan in October 1955 seemed always to focus on the underlying physics of such technology, always driven strongly by the applications needs. This led me to a strong interest in IR systems defined, as was so well stated by Hudson in his book , by the functions to be performed by such systems. To paraphrase his statements, an IR system is defined by what it is supposed to do. Thus the user defines the system-the application determines the system design. As I told Warren, I have developed some rather strong biases concerning the pacing elements of IR components in this context. Unfortunately he said to go ahead and here we are.