Emphasis is on current research and practice, although no period is excluded.
North America is the area of principle interest. Research and pracitces in many other areas are also included.
English language materials receive primary consideration, although works published in other languages are also acquired.
Monographs, serials, environmental impact statements, government publications, dissertations, theses, technical reports, newsletters and microforms are collected.
Audiovisual materials are excluded from the collection. Maps are generally excluded.