Have you returned to Ireland after living / working in Australian on a working holiday visa? If you have worked and paid tax in Australia during the year you are required to submit a tax return.
From 1 January 2017, working holiday makers are subject to a flat rate of tax, currently 15% on the first $37k earned and are exempt from paying the Medicare levy of 2%.
While the system is not as generous as it was in the past, refunds can still be due if you have work related expenses to claim, such as car expenses, tools & equipment used for work, tax agent fees, telephone & internet expenses. For example: