This report presents findings about teacher quality from two longitudinal studies, the National Longitudinal Study of "No Child Left Behind" (NLS-"NCLB"), and the Study of State Implementation of Accountability and Teacher Quality Under "No Child Left Behind" (SSI-"NCLB"). The research teams for these two studies have collaborated to provide an integrated evaluation of the implementation of key "NCLB" provisions at the state level (SSI-"NCLB") and at the district and school levels (NLS-"NCLB"). Together the two studies are the basis for a series of reports on the topics of accountability, teacher quality, Title I school choice and supplemental educational services, and targeting and resource allocation. This is the eighth volume in this report series. Based on findings from the two studies, this report describes the progress that states, districts, and schools have made implementing the teacher and paraprofessional qualification provisions of "NCLB" through 2006-07. Reported findings indicate that: (1) Most teachers met their states' requirements to be considered highly qualified under "NCLB"; (2) The percentage of teachers who were not highly qualified under "NCLB" was higher for special education teachers and middle school teachers, and for teachers in high-poverty and high-minority schools; (3) Despite "NCLB" emphasis on sustained, intensive, classroom-focused professional development, a relatively small proportion of teachers reported taking part in content-focused professional development related to teaching reading or mathematics for an extended period of time; and (4) According to state-reported data for 2005-06, 86 percent of Title I instructional paraprofessionals were qualified under "NCLB." The report concludes that, in general, states and districts are working to implement and comply with the "NCLB" requirements for teacher qualifications: States have set guidelines for highly qualified teachers under "NCLB" and have been updating their data systems. According to states, 94 percent of teachers were designated as highly qualified under "NCLB" in 2006-07, and approximately 94 percent of all paraprofessionals reported holding a qualification that would meet the "NCLB" criteria. States and districts are also working to develop strategies designed to recruit and retain highly qualified teachers, particularly in traditionally disadvantaged schools. Issues recommended for further investigation include: (1) Variations among state policies concerning highly qualified teachers raise questions about whether some states have set high enough standards for teacher qualifications under "NCLB" to ensure that teachers have a solid understanding of the subjects they teach; (2) Variation in teachers' highly qualified status across types of teachers and schools highlights enduring inequities in access to highly qualified teachers; (3) Because many teachers were not aware or notified of their "NCLB" status, they may not have taken necessary steps to become highly qualified; and (4) The low proportion of teachers participating in content-focused professional development over an extended period of time suggests that more can be done to deepen teachers' content knowledge. Four appendixes are included: (1) Description of NLS-"NCLB" and SSI-"NCLB" Methodologies; (2) Supplemental NLS-"NCLB" Exhibits and Standard Error Reports; (3) Supplemental State Exhibits; and (4) Definition of professional Development in Section 9101(34) of the "ESEA" ["Elementary and Secondary Education Act of 1965"]. (Contains 87 footnotes and 139 exhibits.)