This book presents a new exploration environment for mesh-based, heterogeneous FPGA architectures. It describes state-of-the-art techniques for reducing area requirements in FPGA architectures, which also increase performance and enable reduction in power required. Coverage focuses on reduction of FPGA area by introducing heterogeneous hard-blocks (such as multipliers, adders etc) in FPGAs, and by designing application specific FPGAs. Automatic FPGA layout generation techniques are employed to decrease non-recurring engineering (NRE) costs and time-to-market of application-specific, heterogeneous FPGA architectures.