The Typological Database System (TDS) is a web-based service that provides integrated access to a collection of independently created typological databases. It was developed with support from NWO grant 380-30-004 / INV-03-12 and from participating universities, and provides continued availability and extended documentation for its component databases, through a uniform structure and search interface. Note that the more recent source code for a curated TDS, as developed in the TDS Curator project funded by CLARIN-NL, is part of another dataset. Furthermore, the typological databases are separate datasets (see Relations).