New Concepts in Digital Reference Let us start with a simple scenario: a man asks a woman how high is Mount Everest The woman replies 29 029 feet. Nothing could be simpler. Now let us suppose that rather than standing in a room or sitting on a bus the man is at his desk and the woman is 300 miles away with the conversation taking place using e mail. Still simple Certainly.it happens every day. So why all the bother about digital (virtual electronic chat etc.) reference If the man is a pilot flying over Mount Everest the answer matters. If you are a lawyer going to court the identity of the woman is very important. Also if you ever want to find the answer again how that transaction took place matters a lot. Digital reference is a deceptively simple concept on its face: the incorporation of human expertise into the information system. This lecture seeks to explore the question of how human expertise is incorporated into a variety of information systems from libraries to digital libraries to information retrieval engines to knowledge bases. What we learn through this endeavor begun primarily in the library context is that the models methods standards and experiments in digital reference have wide applicability. We also catch a glimpse of an unfolding future in which ubiquitous computing makes the identification interaction and capture of expertise increasingly important. It is a future that is much more complex than we had anticipated. It is a future in which documents and artifacts are less important than the contexts of their creation and use Introduction Defining reference in a digital age So why care about questions The word game Conversations Conversants Language Agreements Memory Knowledgebase problem Looking at the reference transaction as a conversation Digital reference in practice Question acquisition Triage Answer formulation Tracking and resource creation Resource creation Durability of the general digital reference model Digital reference and a new future Scapes Conclusion Acknowledgments References Author biography