3-Dimensional (3-D) integration offers numerous advantages over conventional structures. Double-gate (DG) transistors can be fabricated for better device characteristics, and multiple device layers can be vertically stacked for better interconnect performance. In this paper, we explore the suitable device structures and interconnect architectures for multi-device-layer integrated circuits and study how 3-D SOI circuits can better meet the performance and power dissipation requirements projected by ITRS for future technology generations. Results demonstrate that DGSOI circuits can achieve as much as <italic>20%</italic> performance gain and <italic>8%</italic> power delay product reduction than SGSOI (single-gate SOI). More important, for an interconnect-dominated circuits, multi-device-layer integration offers significant performance improvement. Compared to 2-D integration, most 3-D circuits can be clocked at much higher frequencies (double or even triple). Multi-device-layer circuits, with suitable SOI device structures, can be a viable solution for future low power high performance applications.