This note reprints a 1903 letter against the movement within Britain for protectionism and an imperial trading bloc. The letter is signed by C.F. Bastable, A.L. Bowley, Edwin Cannan, Leonard Courtney, F.Y. Edgeworth, E.C.K. Gonner, Alfred Marshall, J.S. Nicholson, L.R. Phelps, A. Pigou, C.P. Sanger, W.R. Scott, W. Smart, and Armitage Smith, and supported after the fact by S.J. Chapman and J.H. Chapman.