Archival collections have particular properties that make physical and intellectual access difficult for researchers. This generates feelings of uncertainty in the researchers leading to a large burden of routine enquiries to the archive. In this thesis I investigate the information-seeking behaviours of archival researchers and the distinct properties of the archive first through the respective literatures and then through a series of five studies. Using systems, data and researchers from The National Archives, these studies examine the nature of the enquiries that archives receive across many channels; the in-person interactions between archivists and researchers in the reading rooms; and the unmediated search behaviours of archival researchers. I proceed to outline the barriers inhibiting research progress and the techniques or ‘regulators’ used by researchers to surmount or mitigate these barriers. In the final two studies I develop and attempt to validate an instrument for measuring uncertainty in information seeking in large digital collections. This three factor (disorientation, prospect and preparedness) scale of archival uncertainty allows improvements to online archival systems to be effectively tested before implementation. I also propose system properties which seem likely to assist researchers to make progress given these factors and which could be tested using this instrument.
The research for this thesis was funded by the Engineering and Physical Sciences Research Council (EPSRC).