In the period 1982 to 1985, 73 placements of catheter shunts for fetal obstructive uropathy and 44 drainage procedures for obstructive hydrocephalus were reported to a voluntary international registry. The attempts to decompress the obstructed fetal urinary tracts resulted in the survival of 30 fetuses (41 percent), with a procedure-related death rate of 4.6 percent. Pulmonary hypoplasia was the major cause of death in both untreated and treated fetuses. Although the natural history of fetal obstructive uropathy has not been well studied, the outcome of intervention for selected fetuses with posterior urethral valve syndrome was encouraging. The results of shunt procedures for obstructive hydrocephalus were less encouraging. Although 34 of 44 fetuses (83 percent) survived, the procedure-related death rate was 10.25 percent, 18 of the 34 survivors (52.9 percent) have serious neurologic handicaps, 4 (11.8 percent) have less severe handicaps, and only 12 (35.3 percent) are developing normally. Analysis of data from this registry has guided the early development of fetal surgery, but it cannot establish the efficacy of the procedures because of selection bias. A controlled trial is needed.