Namely, very minor adjustments to spending combined with tax increases.
Veronique de Rugy has the details here, for The Los Angeles Times:
"In a 2009 paper, Harvard economists Alberto Alesina and Silvia Ardagna looked at 107 examples in developed countries over 30 years and found that successful austerity packages — defined by a reduction in debt to GDP greater than 4.5% after three years — resulted from making spending cuts without tax increases. They also found that this form of austerity accompanied by the 'right policies' (easy monetary policy, liberalization of goods and labor markets, and other structural reforms) is more likely associated with economic expansions rather than with recessions. This makes intuitive sense: Austerity based on spending cuts signals that a country is serious about getting its fiscal house in order in a way that taxing and spending certainly does not.
"On the other hand, they found that the so-called balanced approach — typically a mix of spending cuts and tax increases — is a recipe for failure. It fails to stabilize the debt, and it is more likely to cause recessionary economic contractions. And when it comes to plans such as Hollande's that would explicitly increase spending and taxes, they find little chance of either economic expansion or debt reduction."
