Web-based online public access catalogues (OPACs) began to appear in the la
te 1990s and many libraries are currently considering implementation. As ca
talogues, they demonstrate advances on traditional OPACs, especially in ter
ms of remote access by users and their potential to integrate many document
types and sources via a single interface. This paper considers some of the
features and functions of Web OPAC interfaces. As yet, very little evaluat
ion of systems and users has taken place and until more such literature app
ears, a general approach to products available is considered to be of value
. Six popular Web OPAC interfaces in use in UK academic libraries (Talis, I
NNOPAC, WebCat, Voyager, GeoWeb and ALEPH) have been examined with an overv
iew of the functions offered via those interfaces. A checklist has been dev
eloped as an indicator of the important features and functions offered.