According to eBrief No. 18/09, with effect from today, the Corporation Tax Assessing System will be incorporated into the Integrated Taxation System (ITS).
The key change you, the Chartered Accountant, will note is that the Notice of Assessment will be presented in a new format, similar to that already in place for Income Tax, incorporating a covering letter, summary calculation information and a fully detailed Notice of Assessment.
In addition, an enhancement to the existing offsetting rules has been provided to prevent a tax credit for VAT or PAYE/PRSI, for example, being prematurely offset against Corporation Tax liability on foot of an assessment where a ROS Debit Instruction has been set up to cover the balance.
eBrief No. 18/09 is available here