At the end of the two-day meeting, the announcement of the outcome will be made at 8am on Thursday.
Keen interest will be taken in the announcement by Fed chairwoman Janet Yellen, who has not briefed the market since September.
Among the things the Fed will consider are:
Oil price
It is hard to see confidence returning to markets until there is some stability in oil prices.
With Brent crude oil falling another 10.6% last week and closing at $US62 ($NZ79.90), the price is now 44% lower than the end of June and back at levels not seen since May 2009.
Financial markets
Last week was a terrible week for equities with further sharp falls in oil prices adding to volatility and keeping investors worked up about when commodity price falls will subside.
The US market had its worst week since May 2012 with the Standard and Poor's index falling 3.5%.
Economy
Economic data in the US still looks solid, with November consumer confidence on Friday beating expectations and hitting its highest level since December 2006.
Interest rates
Markets will focus on whether the phrase ''considerable time'' is left in Dr Yellen's statement.
If it is removed, this will add credence to the view interest rates could start rising mid-next year.
However, the current lack of inflation easily allows the Fed to leave this wording in its statement.
If it is removed. the Fed will cover its bases by noting it has the ability to be patient when it comes to the removal of stimulus.
After this week, the next Fed meeting will be in late January although the next one with a press conference and updated economist forecasts will not be until the middle of March 2015.
