The question arises which GSIM object or set of objects actually describes the building block (Lego brick or Service) as defined in CSPA? It seems that the ProcessStep is the logical choice. As a consequence, it must be possible to combine a particular ProcessStep with any other ProcessStep into a Process. This means that there is no up-front fixed relation between ProcessSteps, and this relation should certainly not be made based on the ProcessStepDesign. It must be possible for one ProcessStep to be followed by multiple ProcessControls, but only one within the context of a particular Process. There is no direct relationship between Process and ProcessStepDesign, a CSPA Assembler creates a new Process by combining available ProcessSteps and ProcessControls.

Are then both ProcessStep and ProcessControl the CSPA building blocks?

Do we need a mechanism to express the specific relationship between a ProcessStep and a ProcessControl within the context of a Process?