Autonomous observatories collecting acoustic data in areas (periodically) inaccessible to humans are a promising tool to advance our knowledge concerning species inhabiting these remote regions. Here we introduce the PerenniAL Acoustic Observatory in the Antarctic Ocean (PALAOA) which was constructed to obtain real-time, year-round broadband underwater acoustic data from the Antarctic coastal ocean. The PALAOA-observatory is located at 70°31S 8°13W, on the Ekström ice shelf, at 1.5 to 3 km distance to the ice shelf edge, Eastern Weddell Sea. The observatory utilizes a hydrophone array deployed underneath the Antarctic ice shelf to autonomously and continuously record the underwater soundscape. The PALAOA-observatory has been operational since January 2006 and has collected a total of 8191 hours of data over 438 days (by November 2007). In this talk, we provide 1) information on the observatorys technical features, 2) an overview of (bio-) acoustic signatures recorded so far, 3) preliminary results concerning cetacean and pinniped species that have acoustically been identified in the PALAOA recordings and 4) an outlook of ongoing and future PALAOA based projects.