In a significant number of marriages, one individual is largely responsible for handling the finances. Often, the other party knows little about family income and expenses. If you intend to divorce, begin to compile the financial information you'll need and get informed. If you've filed a joint return and don't have it, one practical way to begin is by writing to the IRS and asking for a copy of it. That will give your lawyer a good starting place from which to make critical assessments regarding maintenance, child support and property distribution.