This is an arrangement by an individual with his creditors to repay his debts over a period of time to avoid bankruptcy. Generally you will pay less than what the actual debt is.
As you will need 75% majority of the creditors voting at the meeting, it is recommended that you make a good offer subject to your income to have the approval of the creditors. Once the approval is given by the creditors, this will then bind all the creditors including those who did not participate in the voting. After the completion of the arrangement any unpaid debts will be written off.
It must be noted that an IVA only deals with the unsecured creditors as the secured creditors must be paid in full as before. The major advantage of the IVA is that the bankruptcy restrictions do not apply in the arrangement. In the arrangement you may continue to act as a Director of a limited company.