The Health Sciences Libraries Consortium (HSLC) was established in 198
5 by thirteen founding member institutions in Pennsylvania and Delawar
e. In 1989, the Interlibrary Loan, Document Delivery, and Union List T
ask Force, appointed by the HSLC Board of Directors, successfully demo
nstrated the feasibility of supplying 94% of all interlibrary loan (IL
L) photocopy requests in forty-eight hours or less by a network applic
ation of group 3-level memory telefacsimiles. However, the expenses as
sociated with the telefacsimile operation and the limitations associat
ed with network polling protocols challenged participants to seek new
alternatives for ILL. In 1990, the HSLC introduced HSLC HealthNET(TM),
an online wide-area network linking eleven of the thirteen institutio
ns and their resources while providing access to the Internet. The HSL
C HealthNET additionally supports a centralized shared library system,
several locally mounted databases, and consortiumwide electronic mail
. In 1991, a project was initiated to evaluate Ariel(TM) software, pio
neered by the Research Libraries Group (RLG), compared to the existing
network application of group 3-level telefacsimiles. Factors identifi
ed as critical to Ariel's potential to replace the telefacsimile netwo
rk were the proprietary software specifications for Internet access, t
he use of HSLC's existing wide-area network (WAN), and a hardware plat
form that was optimal for an ILL environment. This article describes t
he Ariel project history, the transition to Ariel from the telefacsimi
le network, evaluation of equipment features for processing efficiency
, and operational issues affecting ILL policy.