In the course of the last decades, a wealth of data has been published on the origin and development of grammatical forms. Part of these data, as they were available up to 2002, were published in the first edition of the World Lexicon of Grammaticalization. The main purpose of the present work is, first, to make some revisions to the first edition and, second, to provide an update on some of what has happened in grammaticalization studies since 2002. The update concerns, on the one hand, new, general developments that this field has experienced. To this end, some of the directions that appear to be particularly relevant to the field are pointed out in Section 1.3. On the other hand, the update concerns a wider database, considerably expanded with regard to the distinct language varieties (i.e. dialects included), which are over 1,000, and the processes discussed, which involve 544 grammaticalization paths.