In current wireless communications, radio spectrum and infrastructure are typically used such that interference is avoided by exclusive allocation of frequency bands and employment of base stations. SAPHYRE will demonstrate how equal-priority resource sharing in wireless networks improves spectral efficiency, enhances coverage, increases user satisfaction, leads to increased revenue for operators, and decreases capital and operating expenditures.SAPHYRE represents a consortium that spans the entire chain from spectrum regulatory aspects, networking, physical layer to hardware implementation. The vision of SAPHYRE is to: (i) show how voluntary sharing of physical and infrastructure resources enables a fundamental, order-of-magnitude-gain in the efficiency of spectrum utilisation; (ii) develop the enabling technology that facilitates such voluntary sharing; (iii) and determine the key features of a regulatory framework that underpins and promotes such voluntary sharing.SAPHYRE's main objectives are conceptually described as:1. SAPHYRE will analyse and develop new self-organising physical layer resource (spectrum, spatial coexistence) sharing models by a generalised cross-layer and cross-disciplinary approach.2. SAPHYRE will propose and analyse efficient co-ordination mechanisms which require only small intervention (to counteract selfish, malicious users). In particular in sharing scenarios, incentive based design is applied in order to reduce regulatory complexity.3. SAPHYRE will develop a framework for infrastructure sharing to support quality of service with sufficiently wide carrier bandwidths and competition between different operators.Therefore, modern and novel physical layer techniques, including network and interference aware modulation/ coding, multi-antenna, spatial scheduling, multi-hop, relay co-operative transmission which lead to high spectral efficiency are developed.