This presentation focuses on several examples of partnerships between tool suppliers and embedded software developers in which state-of-the-art tools are used to optimize a variety of electric and hybrid vehicle architectures. Projects with Automotive OEMs, Tier One Suppliers as well as with academic institutions will be described. Due to the growing complexity in multiple electronic control units (“ECUs”) inter-communicating over numerous network bus systems, combined with the challenge of controlling and maintaining charges for electric motors, vehicle development would be impossible without use of increasingly sophisticated tools.Hybrid drive trains are much more complex than conventional ones, they have at least one degree of freedom more. To achieve the development goals (e. g. optimum drive performance and minimum CO2 emissions), an optimal configuration of combustion engine, battery and electric machine(s) can only be defined with the help of computer simulation methods and tools.Even if the major specs (speed/torque characteristics, performance, high voltage system) of all components are defined and fixed, the operating strategy software (overall hybrid drive train coordination) still significantly influences these goals. The hybrid ECU with the vehicle's operating strategy is often developed, implemented and tested by means of desktop simulation, rapid control prototyping, automatic code generation as well as hard-ware-in-the-loop (HIL) simulation. The e-mobility technology is developing very rapidly. So cooperative partnerships between OEMs, component and controller suppliers and test equipment and tools companies can be observed world-wide. For example: Lithium-ion battery suppliers are working in cooperation with controller developers and tools companies on battery simulation and controller testing. Additionally, several trends can be observed in the HEV development area: HIL simulation replaces track tests to handle the complexity and reduce costsOptimization tools are applied on mechanical test benches to automatically find a good compromise between driveability, performance and emissions.This paper presents application examples where these partnerships and new trends lead to successful products in the automotive industry. One special summary example of the use of embedded software development tools is the EcoCar Challenge , an industry-supported project organized by the Department of Energy in conjunction with General Motors, and other sponsors, to develop expertise in the automotive development process, especially relative to producing “Greener” vehicles. In this project, competing Universities are supplied with a base vehicle and software development tools, such as rapid prototyping systems and HIL test systems. Numerous powertrain architectures are developed and optimized during the course of the competition.