Wise and careful selection of materials remains among the most important and enduring duties of the librarian--and also among the most difficult. The author has found this to be especially true in a specialized-subject library, where traditional collection development methods do not always yield good results. While collection development practices must necessarily vary according to subject matter, type of library, budgets, and other factors, many of the tips offered in this article will appeal to a wide variety of librarians seeking to "be complete on something." They can be implemented slowly over time, and often with little or no cost as compared to the status quo. The author believes that building a highly specialized collection is predicated on commitment from the librarian to uncover the best materials, wherever and whatever they may be; to spend funds wisely; to advocate tirelessly for the collection; and to collect and preserve materials for the intellectual communities of today and tomorrow. It may not be possible to be truly "complete" on any subject in today's complex information landscape, but the trying--the journey of discovery that collection development represents--remains one of librarianship's most interesting and intellectual pursuits.