Volume G of International Tables for Crystallography, first published 21 years ago, covers crystallographic data definition and exchange. The second edition, consisting of 50 chapters that are now mostly complete and available online [1], incorporates the significant standards work that has taken place over the last two decades. That work includes: new dictionaries covering twinning, magnetism, topology and restraints; an embedded language for describing mathematical relationships between data names; the NeXus/HDF5 standards; new software; major updates to core and powder dictionaries; and a more powerful CIF syntax. In a further innovation, the CIF standards can now describe data that is spread over multiple data blocks and files. This presentation will provide a tour of the new volume and summarise the most important of these updates.