This lecture is on efficient methods for modeling of complex microelectronic systems that enable a system designer to build large scale simulation models while ensuring realizability into hardware. Recent years have seen a surge of interest in use of object-oriented languages (such as C++, Java) for integrated system modeling as evidenced by growing use of SystemC, Cynapps and SpecC language/libraries. The question, however, remains how an integrated circuit designer is to realize the productivity gains claimed by high-level system modeling languages while ensuring efficient circuit realizations and/or ensuring circuit synthesizability using present high-level/logic-level synthesis technologies. This lecture presents a methodology to use these new languages with object oriented paradigms and shows design examples.