ARM is the main forum for researchers on adaptive and reflective middleware platforms and systems. It was the first ever workshop to be held in conjunction with the ACM/IFIP/USENIX International Middleware Conference, dating back to the year 2000, in Palisades, NY (Middleware 2000). At that time, it was called simply The Reflective Middleware Workshop (RM2000). It has since expanded its scope to encompass other techniques and perspectives to build adaptive middleware systems and applications. In its 13th edition we expect to follow on the path of consolidating ARM as a major and exciting venue for presenting and discussing bleeding edge research on adaptive middleware, its implications for different application domains, and its combination with a plethora of different techniques used to build adaptive systems. In the about section you can find a more complete description of the workshop.