Problem Statement: What do teachers and students in Turkey perceive as the common characteristics of effective physics teachers? Purpose of Study: The first aim was to investigate the common characteristics of effective physics teachers by asking students and teachers about the effects of teacher characteristics on student physics achievement and motivation. The second aim was to explore whether the effects of these characteristics were significantly associated with the geographical region, grade level, and gender of students, as well as with the region, gender, and year of teaching of teachers. Methods: The data were gathered via a questionnaire that was administered to 2,177 high school students and 214 physics teachers in 9 cities from 3 geographical regions in Turkey. A mean score table was prepared, to compare effective physics teacher characteristics. Factor analysis was used to categorize these characteristics. After conducting missing data analysis and identifying descriptive statistics, MANOVA was used to test the null hypothesis. Findings and Results: Teachers perceived teacher characteristics as having a greater effect on student motivation and achievement than did students. The eight main categories of effective physics teacher characteristics each had a strong effect on student motivation and achievement. These characteristics affected student achievement more than student motivation, according to teachers. Female students declared more than male students that physics teacher characteristics affected their motivation and achievement. Mediterranean-region students declared more than students from other regions that these characteristics significantly affected their motivation and achievement. Eleventh grade students declared more than tenth and ninth grade students that these characteristics affected their motivation and achievement. Conclusions and Recommendations: The findings suggested that both students and teachers perceived physics teacher characteristics as affecting student achievement and motivation. The category that included the most effective characteristics was "Pedagogical and Subject Matter Knowledge". Physics teachers should be aware of their characteristics, and the characteristics of teachers should be taken into account in the process of selecting and assigning teachers.