Azerbaijan lies in an extremely propitious position between the Caucasus and the Caspian Sea and has always been an important stop along the Silk Road, and a melting pot of languages and cultures. Many ethnic, religious and linguistic groups passing through or settling in the territories of present-day Azerbaijan historically came into contact with local communities, hence contributing to this linguistic mosaic. Investigating languages of Azerbaijan is interesting and important not only from the linguistic point of view. It also bears a socio-cultural value in that it can offer a new perspective on studying these languages from the standpoint of their vitality and maintenance. This volume offers new data and highly valuable insights into various linguistic and sociolinguistic aspects of the East Caucasian, South Caucasian as well as the Iranian varieties spoken in Azerbaijan. With this publication, we hope to set in motion more linguistic activities and research initiatives on the different varieties forming Azerbaijan’s languages treasure, including Azerbaijanian dialects – many of which display highly interesting features due to contact with the languages presented in this volume.