This multiple case study investigated how teachers implemented motivational teaching strategies and the impact of these strategies on students' motivation in an Indonesian high school context. The participants were four teachers and four groups of their students. The data were collected from teachers by conducting semi-structured interviews, classroom observations, and stimulated recall, and from the students through focus group interviews. The findings of the research indicated that each teacher had unique strategies to motivate their students, and these strategies had a profound impact on students' motivation. The students reported that the strategies influencing their motivation could be categorized into five main groups: teachers' classroom behaviors, supportive classroom atmosphere, selection of learning resources and activities, the usefulness of English, and the way feedback was given. These findings suggest that teachers of English in an Indonesian high school context can influence their students' motivation by understanding the effect of motivational teaching strategies on students' learning and behaviors.