Burton have signed Sheffield United defender John Brayford on a free transfer, and Tottenham striker Will Miller and Rochdale midfielder Jamie Allen for undisclosed fees.
Brayford, 29, has signed a two-year deal, having played 34 games on loan at the Championship side last season.
Miller, 21, has also signed a two year-deal, having scored once in 16 games on loan with the Brewers last season.
Allen, 22, has agreed a three-year contract with Nigel Clough's side.
Find all the latest football transfers on our dedicated page.