If there is a default provision of your settlement agreement (from your divorce), follow it to a T. In other words, the minute he pays less than he's supposed to, send him a default letter (most agreements require same be sent via certified mail, return receipt). There is ample caselaw stating that if he voluntarily quit (& a retirement is construed the same as quitting) he is not entitled to a reduction. Whereupon, you may then file an order to show cause with Supreme Court asking for enforcement. Schedule a consult with a Putnum/Westchester Family Law attorney for a full assessment.  -- David Bliven, Westchester Family Law attorney (www.blivenlaw.net)