This paper presents a tool for assessing teaching presence in online courses that utilize computer conferencing. The tool is based on a model of critical thinking and practical inquiry developed by Garrison, Anderson, and Archer, which defines teaching presence in three categories: design and organization, facilitating discourse, and direct instruction. The authors describe the theoretical framework and provide a detailed classification of teacher roles in computer conferencing. They also introduce a method for analyzing transcript data using content analysis, focusing on indicators of teaching presence. Preliminary results from analyzing transcripts of two graduate-level online courses show significant variations in the extent and type of teaching presence. The study highlights the importance of teachers' active involvement in creating and sustaining a positive learning environment, and suggests that the tool can be used to improve teaching practices and support research in online education.This paper presents a tool for assessing teaching presence in online courses that utilize computer conferencing. The tool is based on a model of critical thinking and practical inquiry developed by Garrison, Anderson, and Archer, which defines teaching presence in three categories: design and organization, facilitating discourse, and direct instruction. The authors describe the theoretical framework and provide a detailed classification of teacher roles in computer conferencing. They also introduce a method for analyzing transcript data using content analysis, focusing on indicators of teaching presence. Preliminary results from analyzing transcripts of two graduate-level online courses show significant variations in the extent and type of teaching presence. The study highlights the importance of teachers' active involvement in creating and sustaining a positive learning environment, and suggests that the tool can be used to improve teaching practices and support research in online education.