Best-Reliable Ambient Intelligent Nanosensor Systems – e-BRAINS – represent a giant leap for outstanding future applications in the area of ambient living with the ultimate need for integration of heterogeneous technologies, high-performance nanosensor devices, miniaturization, smart wireless communication and best-reliability.e-BRAINS with minimum volume and weight as well as reduced power consumption can be utilized in ambient living systems. Successful market entry of such innovative ambient intelligence products will be determined by the performance improvement achieved and the cost advantage in relation to the total system cost.The basic requirement for robustness and reliability of the heterogeneous integration technologies and the nanosensor layers is in the focus of all e-BRAINS developments.The designated nanosensor systems represent a very promising innovative approach with the potential to enable high-performance and precise functions in new products. The application of nanotechnology will allow large improvements in functionality and will open a wide range of applications for European companies.Future e-BRAINS applications require significantly higher integration densities. Performance, multi-functionality and reliability of such complex heterogeneous systems will be limited mainly by the wiring between the subsystems. Suitable 3D integration technologies create a basis to overcome these drawbacks with the benefit of enabling minimal interconnection lengths. In addition to enabling high integration densities, 3D integration is a very promising cost-effective approach for the realization of heterogeneous systems.Besides the heterogeneous system integration the main criteria of e-BRAINS is the need for miniaturized energy storage/delivery systems, low power consumption, smart communication and methodology for reliability and robustness.e-BRAINS benefits from the established European 3D technology platform as major result of the IP e-CUBES.