Synthetic Biology – the design of increasingly complex biological systems according to principles recruited from classical engineering disciplines – is undergoing a rapid expansion from its founding fields – such as the design of biological circuits – into the broad realm of academic and industrial bioengineering. Driven for example by amazing developments in DNA synthesis and assembly, genome engineering, computer-aided design resources, and the ever increasing arsenal of parts and tools, more complex designs are implemented up to the full re-design of eukaryotic chromosomes. On the other hand, crucial developments for systems design, such as minimal and orthogonal systems and in vitro designs, are taking place. The rapid conceptual and technological advance is also reflected in increasing reception of the field in industry and the emergence of major centers of academically driven research and development and entrepreneurship. The 2015 Gordon Research Conference on Synthetic Biology will present cutting-edge research from this rapidly developing field and provide an in-depth discussion forum among practitioners from academia and industry of the various fields contributing to Synthetic Biology. We will work towards identifying crucial scientific, but also societal challenges for the coming years, and towards laying the basis for future developments and consolidation of the field towards fulfilling the envisaged – and ambitious – goals. In addition to bringing together a collection of investigators who are at the forefront of their field, this conference offers excellent opportunities for junior scientists and graduate students to present their work in poster format and exchange ideas with leaders in the field. The collegial atmosphere, with programmed discussion sessions as well as opportunities for informal gatherings in the afternoons and evenings, provides an avenue for scientists from different disciplines to brainstorm and promotes cross-disciplinary collaborations in the various research areas represented.