Findings from four lines of inquiry that attempt to identify teaching skills are reviewed. Following a brief introduction, the first section discusses definitions of "skill" and outlines empirical attributes of teaching skills. In the following section, the four lines of inquiry are described. Results are analyzed in the third section. First, naturalistic studies--analyzing teaching and instructional management in "regular" classrooms, and often deriving experimental models of effective teaching--are reviewed. Second, theory-driven studies--positing particular educational environments as affecting specific types of learning and analyzing the skills used to create such environments--are examined in four subcategories: social models, involving group inquiry by students; information-processing models, emphasizing techniques designed to improve cognition; student-centered models; and behavioral models. Third, examples of curriculum research are reviewed. This research asks whether there are reproducible techniques for producing curricula that affect learning, and whether schools can foster sufficient stability for these curricula to succeed. Finally, effective schools research is considered; it inquires into what types of school environment benefit learning, and how educators produce such environments. The final section briefly summarizes the findings of all four research avenues, assesses their value, and suggests an integrative framework. An extensive bibliography is included. (MCG)