Thieme began publication of Science of Synthesis in 2000, and it is planned to occupy 49 volumes by its completion. About six new volumes are published each year. Each volume covers a specific class of compound. The series is organized into Categories, which are in turn broken down into narrower specialty volumes.
The complete PDF full text of the 4th Edition of Houben-Weyl (1952-2003, in German or English) is also available through the online Science of Synthesis. It is not searchable in the same way as the new edition is; access is mainly by browsing the tables of contents, or by selecting from graphical representations of families of molecules and functional groups. Chapters of the new 5th edition also contain links to related information found in the 4th edition.