A data set from the metalloproteinase deuterolysin was collected at atomic resolution (1.0 A) with synchrotron radiation. The high resolution allowed the structure to be solved with the new direct-methods program ACORN using the coordinates of the Zn atom as a starting point. The phases obtained from ACORN were of sufficient quality to allow automated building to be carried out in ARP/wARP. Minimal manual rebuilding of the model was required and the structure determination was completed using the maximum-likelihood refinement program REFMAC. The whole process, starting from the processed and merged data and ending with a refined model, required less than 6 h of computational time.