Professor John McWhorter spent the months of August and September, 2005, at the Department of General Linguistics, University of Helsinki. He participated in the conference "Approaches to Complexity in Language" and delivered two plenary papers there. The conference was organized in collaboration by the Department of general linguistics and the Linguistic Association of Finland (cf. http://www.ling.helsinki.fi/sky/tapahtumat/complexity/complexity.shtml). A volume from the conference, edited by Miestamo / Sinnemäki / Karlsson, is now ready for publication by Mouton de Gruyter and will appear in January 2008 (including papers by McWhorter, Miestamo and Sinnemäki). In addition, prof. McWhorter taught a postgraduate course on Creoles at the department, with an attendance of 14 doctoral students, most of them from the graduate school "Langnet". Furthermore, he collaborated on language complexity with Matti Miestamo, Kaius Sinnemäki and Fred Karlsson, greatly aiding the advancement of especially Sinnemäki's doctoral dissertation.