Listed below are the titles and authors for the poster presentations at the Symposium. Abstracts for these papers, and in some cases the posters themselves, can be obtained from the Symposium website, www.phys.unsw.edu.au/iau221. For each entry, the first number is the display order of the posters, as listed in the Abstract book for the 25th IAU General Assembly. The second number listed on each line is the IAU GA Reference number, assigned on submission of the abstract, and as listed on the above website.