Left: Crystal engineering allows us to proceed from local design to the control of collective behaviour in order to rationalize the design of metallo-organic materials with flexible dynamic frameworks, able to create pores on demand to accommodate small guest molecules. (Courtesy of Alessia Bacchi) Right: A cryo-electron microscopy structure of the E. coli co-translational targeting complex and the corresponding quasi-atomic model (below) of the signal recognition particle (green-yellow/orange) and its receptor (pink). (Courtesy of Christiane Schaffitzel) Bottom: End-on view of the cryo-EM structure of the bacterial surveillance complex Cascade showing the location of the crRNA. (Courtesy of Eva Nogales)