When Phyllis Weber learned earlier this year that a two-year-old child had died of brain disease in a San Francisco hospital, she immediately dialed a 24-hour alert number in Pittsburgh. The child's liver was still in good condition but would quickly deteriorate, and Weber, who is director of the Northern California Transplant Bank, had only a few hours to find someone who could use it. The voice she reached at the headquarters of the National Association of Transplant Coor- dinators (NATCO) wasted no time getting to the particulars:
"Age of donor?" it asked.
"Two years," Weber replied.
"What is the baby's...