The new rules would allow city and state education officials to swiftly and permanently remove incompetent principals from the school system.

Ms. Feldman said the union supported ways to make it easier to oust incompetent principals and teachers, but without toying with tenure.

In the 16 particularly troubled high schools, he is seeking the power to remove incompetent principals and reshuffle teachers, with or without cooperation of superintendents.

Mr. Singer has repeatedly said he believes the procedures are adequate for removing incompetent principals.

Mr. Giuliani says that tenure protects incompetent principals, while the union says it is a defense against politics and favoritism.

By March, he'd won the right to remove incompetent principals - like the one in the Bronx who had been convicted of possessing crack cocaine.

Even dismissing incompetent principals will not turn the whole system around.

City leaders, however, paint the exodus in positive colors, saying it reflects the efforts to rid the system of incompetent principals.

He persuaded the principals' union to allow him to move incompetent principals from their schools, but only after a hearing.

Nevertheless, Mr. Sasserath says, with all its faults, the licensing system gives some protection against incompetent principals.