Among the main themes of his research are digital libraries; information-seeking behaviors; and interaction between humans and information retrieval systems.
Belkin realized that in many cases, users of search systems are unable to precisely formulate what they need.
He graduated from the same college in Library Science 2 years later (1970), and read his doctoral thesis in 1977 in the University of London.
Nicholas Belkin has approached information retrieval from the so-called cognitive models , that is, those focused on users who access document systems.
In this, Belkin defines a set of interactions that occur between the user and the system during the consultation to "conceptualize, label and transcribe the need for information, as well as make relevant judgments about one or more documents."
Belkin has published numerous articles in the most prestigious magazines in the field of Information and Documentation, some awarded by the ASIST.