The RASNZ Occultation Section has promoted a series of symposia on occultation science alternately between Australia and New Zealand annually since 2007. Continuing in this tradition, the Occultation Section is promoting the 12th Trans-Tasman Symposium on Occultations - TTSO12 - in conjunction with NACAA 2018 in Ballarat. The Monday symposium will include presentations by Australian and international speakers on occultation science, observation results, developing techniques for occultation observation, and the sharing of experiences and learnings. There will be a dedicated tutorial session on the use of occultation specific software and opportunities for informal networking and impromptu help and training.