  Preliminary evidence on the long--run trajectory of the accelerator industry
suggests that it may be close to the maturity phase of its cycle. If this is
the case, how can we measure the benefits of an uncertain breakthrough in
acceleration technology? Who are the main stakeholders interested by such a
breakthrough? We identify these subjects and sketch some avenues for answering
these questions. We thus present a model for the social Cost-Benefit Analysis
(CBA) of research infrastructures and illustrate the results of its
implementation for assessing the benefits of accelerators in basic science and
hadrontherapy. Lastly, we move from the social CBA of single research
infrastructures to modeling a major change in the accelerator technology and
hence in the industry. A research agenda on the potential impacts of a
technological breakthrough is presented.
