The goal is half a million dollars – and the penny-pinching will begin immediately.

Selectmen on Tuesday unanimously backed an agreement hammered out between Town Administrator Derek Sullivan and the state Department of Revenue to “freeze discretionary spending or allow the town administrator to implement an austerity plan” with the goal of reducing expenditures by $500,000 between now and the June 30 end of this fiscal year.

As Sullivan explained it, the agreement gives state revenue officials adequate confidence in Wareham’s finances to set the tax rate this week, allowing tax bills to go out on schedule and tax revenue to come in on schedule.

The Department of Revenue “is still working to gain confidence in the finances of the town,” Sullivan said. Relations between Wareham and DOR officials have been strained in recent years by less than clean audit reports, a string of personnel changes in the accounting department and – most notably – a $900,000 discrepancy in the town’s 2010 books that was never more specifically explained than “bookkeeping errors.”

The new austerity plan’s impact on town and school services was not immediately clear. Sullivan said after the meeting that his preference would be to hit the target through a freeze on all discretionary spending and that he would like to stay away from staff cuts.

Selectmen were clear that the pain had to be shared with the School Department. School spending accounts for about 65 percent of the town budget.

“Every department is included here,” Selectmen Steve Holmes stated. “All departments. Every department that takes a dollar bill.”

Sullivan agreed without elaboration. After the meeting he said Superintendent of Schools Kimberly Shaver-Hood would be discussing the austerity measures with the School Committee Wednesday night.

Sullivan prefaced his presentation of the austerity measures with the explanation that Wareham's base problem is that the expense of continuing to provide existing services is rising faster than the town's tax revenues.

With additional tax revenue, from either a growth in the town's base of taxable property or an increase in taxes above the Proposition 2-1/2 limits, the town must each year fill the gap between revenue and expenses with some combination of grant money and budget cuts.