How can researchers explore the vast space of possible genomes to build strains for bioengineering goals? Presented in Nature Communications is one answer to that question: SCRaMbLE – Synthetic Chromosome Rearrangement and Modification by Lox-P mediated Evolution.   Built into the architecture of the synthetic chromosomes being constructed as part of Sc2.0, SCRaMbLE allows for the rapid rearrangement of chromosomes allowing for selection by end product titre and tolerance to stressful conditions.  The papers presented here (www.nature.com/collections/ncomms-syntheticyeast) are the first set to demonstrate the power of this technology and the applicability to metabolic engineering, synthetic biology and industrial biotechnology.