Discrete element method (DEM) simulation of granular flows has attained a degree of maturity that is consistent with application to the modelling of commercial-scale processes. Modelling of tumbling mills (SAG/AG or ball) was one of the first industrial applications of DEM and continues to be a major focus of technology developers. Despite this, industry makes limited use of mill modelling. This is partly due to issues of confidence in the technology and barriers to access resulting from the often prohibitive cost of obtaining and running DEM simulation packages. In an attempt to overcome some of these problems, a Web-based interface to CSIRO's DEM capabilities has been developed. This interface, referred to as webGF-Mill(R), allows users to specify mill simulations that are then performed promptly using CSIRO software and computing facilities. Results are provided to users electronically and can be employed to better inform decisions about new designs or how best to operate an existing mill. Apart from making the benefits of DEM mill modelling more readily available to industry, it is hoped that webGF-Mill(R) will play a significant role in fostering interaction between the users and developers of DEM technology, and consequently increase its value to commercial mill operators. Crown Copyright (C) 2004 Published by Elsevier Ltd. All rights reserved.