The Species 2000 & ITIS Catalogue of Life is planned to become a comprehensive catalogue of all known species of organisms on Earth. Rapid progress has been made recently, but please note that the covered species are probably just slightly over 2/3 of the world's known species. This means that for many groups it continues to be deficient, and users will notice that many species are still missing from the Catalogue.\nThe present Catalogue is compiled with sectors provided by taxonomic databases from around the world. Many of these contain taxonomic data and opinions from extensive networks of specialists, so that the complete work contains contributions from more than 3,000 specialists from throughout the taxonomic profession. Species 2000 and ITIS teams peer review databases, select appropriate sectors and integrate the sectors into a single coherent catalogue with a single hierarchical classification. It is planned to introduce alternative taxonomic treatments and alternative classifications, but an important feature is that for those users who wish to use it, a single preferred catalogue, based on peer reviews, will continue to be provided.\nAs a new development started in 2010, there has been a change in data assembly procedure and in published editions of the Catalogue. This is part of a process in the EC 4D4Life and i4Life projects to bring the Annual Checklist and Dynamic Checklist into unified workflow - The Catalogue of Life. The CoL Workbench tool has been used for data harvesting and final processing of the Catalogue of Life editions since September 2011.