This research reports on the characteristics of middle level teachers, their work environment, their professional and academic preparation, their leadership roles, and their competency levels as perceived by their principals. The research design was constructed as the third of three "decade studies" which focused on middle level schools and were sponsored by the National Association of Secondary School Principals. The previous studies were in 1982 and 1991. Trend data are addressed. Consistent with previous studies, middle level schools were defined in the 2000 study as those serving young adolescents in any combination of grades five through nine. Principals of all middle level schools in the United States were invited to participate in the online survey. Over 1,400 principals completed the questionnaire. Survey questions addressed four major areas relative to middle level schools: context and environment, leaders and leadership structures, curriculum, and school improvement practices. This paper extracts the data specific to teachers from each of those major areas. Implications are discussed and recommendations made with reference to the recruitment of future middle level teachers, the needed expansion of their knowledge base regarding the specific developmental needs of early adolescents, the development of skills required to be effective as members of a grade level team, the knowledge required to develop interdisciplinary curriculum, and their training as teacher leaders. (Contains 34 references.) (Author/SM)