It's Ba-ack. . .

At the third National Education Summit, held in Palisades, New York, in October, the topic du jour was how to improve the quality of America's teachers. After much jawboning by the 100 or so state governors, business leaders, and educators gathered for the conference, participants issued a raft of recommendations, including one that had the feel of déjà vu: link teachers' pay to their performance and skills.

Merit pay, it seems, is back. One of education's hottest ideas in the 1980s, it stalled in the '90s under the weight of opposition and its own failures. Teachers balked at tying salaries to the seemingly subjective evaluations done by principals, and school systems dabbling with new pay schemes typically ran short of money, forcing them to cap the number of teachers receiving the extra pay.

But now, policymakers, school officials, and even teachers' unions are rethinking salary structures. Some of the impetus comes from new research that underscores the importance of good teaching to student learning. It also stems from concerns over quality--pay incentives may persuade good teachers to remain in the classroom--as well as the notion that teachers, like students, must be...