This article addresses some of the scientific, conceptual, and technical impediments to the timely progress of research on the topics discussed in the workshop. This is a young field of scientific exploration. Most of what has been accomplished thus far is a series of efforts at descriptive research; little truly experimental research has been published. There is, however, abundant information on the methodologic difficulties and other dilemmas encountered in these research efforts in a recent special issue of Alzheimer's Disease and Associated Disorders (Holmes et al., 1994).