Growth hormone (GH) and insulin-like growth factors (IGFs) play a central role in skeletal growth and bone remodeling. In vitro, both agents display anabolic properties, and patients with acromegaly exhibit increased bone mass. Recent in vivo studies have demonstrated profound activation of bone remodeling that lasted for months after a single 1-week dose of GH or IGF-I. Despite these positive effects, the few clinical studies conducted with GH in osteoporotic patients have shown disappointing results in terms of bone mass changes. Changes in dosing regimens and other adjuvant therapies may, however, lead to more efficient use of these agents.