Interstate dispute settlement authorities (IDSAs) require administration by means of so-called registries or secretariats. These entities are entrusted with tasks that help the respective IDSA in discharging its function as a judiciary. A comparative analysis of selected IDSAs’ Statutes and Rules of Procedure reveals that the tasks assigned to registries or secretariats are not uniform for all IDSAs. There rather exist two different modes of work, with one being exclusively administrative and the other being supplementary consultative. This chapter sheds light on the origins of the consultative mode of work in the IDSAs’ Statutes and Rules of Procedure. It is argued that adjudication through dispute settlement requires legal and non-legal information to be processed by some means of information management within the course of court proceedings. Pre-judicial proceedings encompass joint information management by the disputing parties before adjudication takes place. In this case, IDSAs’ registries’ and secretariats’ statutory rules prescribe only an administrative mode of work. In contrast, for IDSAs in which pre-judicial proceedings are not foreseen, information management needs to take place in the course of court proceedings and hence is conducted by the respective judiciary. This information management is carried out in cooperation with their secretariats or registries. In this case, IDSAs’ registries’ or secretariats’ statutory rules prescribe a consultative mode of work. A correlation between the existence of pre-judicial proceedings and the absence of respective registries’ or secretariats’ consultative modes of work is deduced from a comparison of eight different IDSAs. In conclusion, positive aspects of joint information management by the disputing parties are highlighted and best-practice examples for the integration of joint information management by disputing parties for ISDAs which do not foresee pre-judicial proceedings are indicated.