The Z39.50 search and retrieval protocol provides the opportunity for the creation of a common user interface across library management systems supplied by different vendors. It further offers the advantage of being able to search these different systems simultaneously and the term 'clump' has been given to the bringing together of diverse library catalogues inthis way. International work has been undertaken on virtual catalogues and in the UK the eLib programme funded investigations into four clumps starting early in 1998.

RIDING: Z39.50 Gateway to Yorkshire Libraries, is one of the clump projects being undertaken by a consortium of the Yorkshire and Humberside Universities Association, Leeds Library and Information Service, the British Library Document Supply Centre and Fretwell-Downing Informatics. At the technical level, the intention is to investigate the potential of Z39.50 by creating a Gateway for access to eleven library catalogues. Whereas the creation of this clump displays useful information about the holdings in the region not previously available in a co-ordinated manner, it does not by itself provide any improved service to library users.

The RIDING Consortium is taking positive strides to create real services from the potential of clumped catalogues. From access to catalogues, it is argued, users should be able to move seamlessly to access to materials. For this reason, inter-library loan between RIDING institutions is an integral facility, permitting the end-user to request a loan of any item located via the Z39.50 search (the ILL being mediated by library staff). For physical access a RIDING Access Policy has been agreed and this will provide not only free access to staff and accredited researchers across all academic and public library members of the RIDING Consortium but also free borrowing facilities.