Process composition, Process performance models etc. are terminologies in CMMI High Maturity area. Process needs to be composed quantitatively considering various alternatives to achieve the project performance objective. There needs to be a linkage between composed process and PPM. Or rather there needs to be alternative methods for the critical sub processes in the PPM. It means there needs to be a number of PPMs too. i.e. If customer feedback score is the objective and number of acceptance testing bugs, code review defect density, schedule variance in requirement analysis etc are the subprocesses in PPM , then to compose the process of code review or requirement analysis, there needs to be various alternatives. Say for example code review could be done by peer review or expert review, like that. Similarly for other subprocesses. Then there will be different PPMs built with different alternatives in an organization unless otherwise the data from all alternatives altogether forms a stable process.. So is there a chance to have PPM in single, since data pertaining to each alternative would be different?