Researchers at NIET and elsewhere have studied the effectiveness of "TAP: The System for Teacher and Student Advancement" (TAP) in raising student achievement, improving the quality of instruction, and increasing the ability of high-need schools to recruit, retain and support effective teachers. This document provides summaries of some of the key studies on the TAP System to date. It is divided up into the following sections: (1) NIET Mission; (2) TAP: The System for Teacher and Student Advancement Description; (3) TAP Impact in Schools, Districts and States; (4) Student Achievement (Nationwide, Indiana, Louisiana, Texas, Arizona); (5) Teacher Retention; (6) Educator Attitudes; and (7) References.