SLLS has reached an agreement with the GGKG (Gesellschaft für Gebärdensprache und Kommunikation Gehürloser, Eng: Society for sign language and deaf communication)  in Germany: SLLS members receive a substantial discount when becoming GGKG member. Membership includes the three-yearly journal Das Zeichen, a rich source of information in the German language area, including not only reports of ongoing and completed research projects, but also news items and discussions related to deaf culture, sign teaching and interpreting.

The international GGKG membership fee for SLLS members is €34 (regular 54). The membership also includes a 20% discount to all publications of Signum Press, who also publish many English books on sign language and related topics.