While fitting these in with your existing regime might take some serious thought, you're already sure it will be worth the effort.
Times, Sunday Times (2010)
The Treasury wants to replace the existing, hugely complex regime with a much simpler one with a much lower annual allowance.
Times, Sunday Times (2010)
But there was agreement that change was essential and, increasingly, a sense that the existing regime had to go.
World History: Patterns of Change and Continuity (1995)