As a source of information on neuroanatomical research methods this Volume is not without precedent. In 1957, at the initiative of Dr. W. F. Windle, a conference was held at the National Institutes of Health, the proceedings of which, edited by Dr. Windle and published by C. C. Thomas under the title "New Research Tech­ niques of Neuroanatomy", rapidly became something like a standard reference in the field of Neuromorphology. The present editors were emboldened to seek support for a second expose of contemporary research methods in Neuroanatomy by the success of this earlier publication, as well as by the consideration that the years elapsed since its appearance have been, perhaps, more productive of new research methods and strategies in Neuroanatomy than were any dozen consecutive years since the golden decades of the 1870's and 1880's. The decision, which methods to include in this conference, has been a difficult one. For reasons of space alone it would have been impossible to do equal justice to techniques approaching the brain as a neuronal system, the brain as a tissue, or the neuron as a cell. As a brief inspection of the contents of this volume will show, the weight of choice fell upon the first of these alternatives. The reader will find, further­ more, that not all of the book is devoted to new methods in the strict sense.