Management control of a herd of animals is undertaken even at the most primitive level by recording data and subsequently recalling the information to effect decisions. This was true of the shepherd and goatherd of antiquity and the techniques used then were not much improved until the 1930's when an impetus for change came from setting up such bodies as the Milk Marketing Board. With dairy cattle, the major emphasis is now on herd control using methods equivalent to management control in industry. In management control, an aggregate of data, retrieved by suitable analysis, is used to effect a policy decision.