1. A computer program product stored on a computer usable medium, comprising computer readable program coded instructions for causing a computer to perform a method for computer-assisted comparative assessment of process maturity of business processes when said program is run on said computer, the product comprising: a first medium portion comprising code programmed to define a plurality of categories and, for each of said categories, defining a plurality of criteria indicative of maturity ratings for a process; a second medium portion comprising code programmed to map said criteria onto a binary decision tree, wherein each node of said binary decision tree comprises a data structure in a computer providing a plurality of subscores for a corresponding criterion and wherein defined criteria within a category comprise dependencies to each other; a third medium portion comprising code programmed to query a binary input for each of said criteria and providing subscores dependent on values of said binary inputs; a fourth medium portion comprising code programmed to calculate a final score representing maturity of the process, based on said subscores; and a fifth medium portion comprising code programmed to interlink at least two nodes of the binary decision tree with regard to said dependencies to enforce specific binary inputs required due to said dependencies.