One out of every five nonprofits created today is thought to be the result of restructuring. A word that usually strikes fear, restructuring is often synonymous with a reduction of paid staff or fundamental changes in how an organisation is run. What about the nonprofit sector? Have nonprofits also been caught up in the mania for profitability at any price in an increasingly competitive environment? Is there a critical size for these organisations below which their long-term viability is at risk? We try to identify the main reasons why nonprofits have been merging. We then present the various possible forms of cooperation and mergers as well as the existing legal and tax constraints.