This study has been important in establishing synthetic human parathyroid hormone 1-34 (PTH) as a beneficial treatment for hypoparathyroidism, superior to conventional therapy with calcium and calcitriol. Providing synthetic human parathyroid hormone 1-34 (PTH) to patients who are unresponsive to conventional therapy has enabled severe cases of hypoparathyroidism to be managed effectively with the investigational drug, PTH. The primary goals of this study are to (1) provide long-term PTH therapy to patients who do not respond to conventional therapy; (2) understand the long-term effect of therapeutic PTH replacement on kidney function and bone mineral density; (3) study and track linear growth and bone accrual in children with hypoparathyroidism. (4) determine if subjects reach a normal level of peak bone mass and if the timing of this is comparable to normal age-matched healthy controls.