(1) (Business Process Specification Schema) A subset of the UN/CEFACT Modeling Methodology (UMM) that is used to develop ebXML software. The UMM is used to model business processes and information, but is too generic to be evaluated by ebXML-compliant software. The BPSS provides a bridge from UMM to specifying ebXML programs. Both UML and XML versions of BPSS are available, the latter being the one that can be readily converted into runtime software. See ebXML.