The librarian's guide to genealogical services and research

I meet four times a year with a group of librarians who are in charge of their library's genealogy (and usually local history) services. A surprising number of them essentially fell into the role, without much or any background knowledge to prepare them. I would strongly recommend this book for such people. It covers the basics of genealogical research, including where to find information, how to judge the reliability of the various sources, building a case with the evidence available, the importance of proper citation, etc. I came to this job already trained as an historian and experienced with genealogy, so it was less helpful for me, but even so it offered a step-by-step review, which was more helpful than I'd expected.