The evaluation of the concept of a translating computer interface for simplifying operation of multiple, heterogeneous online bibliographic retrieval systems has been undertaken. An experimental retrieval system, named CONIT, was built and tested under controlled conditions with inexperienced end users. A detailed analysis of the experimental usages showed that users were able to master interface operation sufficiently well to find relevant document references. Success was attributed, in part, to a simple command language, adequate online instruction, and a simplified naturallanguage, keywordhtem approach to searching. It is concluded that operational interfaces of the type studied can provide for increased usability of existing systems in a cost effective manner, especially for inexperienced end users who cannot easily avail themselves of expert intermediary searchers. Furthermore, more advanced interfaces based on improved instruction and automated search strategy techniques could further enhance retrieval effectiveness for a wide class of users.