Recent work at the University of Edinburgh has aimed to enhance the us
e of performance models and to make such models more accessible to non
-expert users such as designers. This work, part of the Integrated Mod
elling Support Environment (IMSE) project supported by the CEC, result
ed in the development of a tool for creating and running experiments w
ithin a performance modelling context. This paper describes the main f
eatures of this tool, the Experiment, and the support environment with
in which it was developed. We also explain how these features provide
a new level of support for the performance model user.