This chapter establishes a concept of allocation of information granularity regarded as an important design asset in system modeling by giving rise to granular models. It discusses protocols of allocation of information granularity throughout the system and the ensuing optimization. In system modeling, an allocation of information granularity elevates the existing models, no matter what their origin is, to a new level that could be referred to as granular models. The chapter represents that the mapping itself can be realized in various ways depending upon its original realization and a way in which information granules. It deals with a plethora of modeling constructs with some representative. An allocation of the available information granularity can be realized in several different ways depending on how much diversity one would like to consider in the allocation process. An allocation of information granularity can be realized with respect to the parameters of the mapping but in a different scenario as presented so far.