This communication describes the methods used and results obtained with a 21-year-old Standardbred sire bred, using artificial insemination techniques, to a book of 108 mares during the period 11th September to 16th March, 1979-80. A positive pregnancy test rate of 93.5% was achieved. Those mares becoming pregnant averaged 4.6 inseminations per pregnancy (range 1-13). Barren mares, maiden mares and wet mares, irrespective of age, all achieved highly satisfactory pregnancy rates and it was noted that breeding through the January/February period improved the ultimate success rate markedly. When the official returns for the breeding season under review were returned the sire had a live foal success rate of 84%.