The years of ?happy scaling? are over and the fundamental challenges that the semiconductor industry faces, at both technology and device level, will impinge deeply upon the design of future integrated circuits and systems. It is widely recognised that variability in device characteristics and the need to introduce novel device architectures represent major challenges to scaling and integration for present and next generation nano-CMOS transistors and circuits. This will in turn demand revolutionary changes in the way in which future integrated circuits and systems are designed. Strong links must be established between circuit design, system design and fundamental device technology to allow circuits and systems to accommodate the individual behaviour of every transistor on a chip. Design paradigms must change to accommodate this increasing variability. Adjusting for new device architectures and device variability will add significant complexity to the design process, requiring orchestration of a broad spectrum of design tools by geographically distributed teams of device experts, circuit and system designers.