This book thoroughly analyzes the fundamental problem of programmable interconnect design in FPGAs. Recent changes in fabrication technology have caused a renewed interest in this problem that was formerly considered largely solved. Besides presenting some of the most recent research results directed towards resolving the difficulties of programmable interconnect design in scaled technologies, the author also gives a modern introduction to programmable interconnect design in general, covering related topics such as broader FPGA architecture, CAD, and Networks on Chip, enabling practitioners from other fields to understand the significance and implications of this important problem. Introduces a new physical modeling framework to capture the effects of resistance scaling at advanced technology nodes; Presents several new algorithms that allow effective automation of programmable interconnect design; Enables diverse readers to understand FPGA architecture and CAD, and in particular programmable interconnect design.