238 women were randomized between 55 and 85 years of age to receive either: (1) PTH for 1 year followed by alendronate for 1 year; (2) PTH and alendronate for 1 year followed by alendronate for 1 year; (3) alendronate for 2 years; or (4) PTH for 1 year followed by placebo for 1 year. The primary endpoints are changes in bone mineral density at several sites and changes in biochemical markers.