Publisher Summary This chapter discusses several design aspects that will help hardware and firmware work more efficiently to increase performance and reduce unnecessary waiting. In an embedded system, hardware and firmware each have their respective jobs to do but must work together as a system. Coordination must occur between hardware and firmware, especially to keep both working optimally. However, if the system is not balanced, performance could be impacted if firmware is waiting and vice versa. This chapter covers several aspects of hardware design. In the first section, the importance of ensuring that firmware was notified of any pertinent event that occurred in the block is presented. Also discussed are various ways of how firmware could know the task in the block was done. In the second section, it is discussed that how designs can impact the performance of the hardware/firmware interaction. It is then emphasized that how aspects of power-on and how firmware is not alive yet so the blocks must be designed to be self-sufficient until firmware can take over. The last section gives several ways of making more efficient the ability for firmware to communicate with and control the block.