Researchers from Harvard and Wake Forest report finding a plentiful source of stem cells in amniotic fluid. They claim that the stem cells drawn from amniotic fluid which was donated by expectant mothers holds much the same promise as human embryonic stem cells. Dr. Robert Lanza, who is a major supporter of embryonic stem cell research said that the work of these scientsts "represents a giant step forward for stem cell research."
The difference is that using the stem cells from amniotic fluid is ethical while killing an embryo in order to acquire his stem cells is not ethical.