This study explored cognitive, affective, and behavioral engagement in language learning among Omani English as a foreign language (EFL) students. It investigated the relationship between students' engagement and their academic performance and the effects of gender on this relationship. Finally, it explored whether there are any statistically significant differences between students' and teachers' perceptions of students' engagement. The study included two samples: 703 Omani Grade 11 students, both male and female; and 55 EFL teachers in PostBasic Education schools. Convenient sampling was the way executed for selecting both samples from Al-Dahira governorate schools. Quantitative data were obtained through questionnaires administered to students and teachers, whereas qualitative data were obtained through interviews with six EFL teachers. Analysis of students' responses showed that these Omani EFL students were highly affectively and behaviorally engaged in the English language classroom, but they were not that engaged cognitively. They also revealed a statistically significant correlation between students' engagement and their academic performance. There was no statistically significant difference in overall engagement based on gender. However, female students demonstrated higher cognitive engagement than male students. In addition, EFL teachers perceived their students as highly behaviorally and affectively engaged. The teacher interviews revealed techniques teachers used to assess and enhance students' engagement as well as factors that influence students' engagement in the Omani context. Finally, there were no statistically significant differences between students' and teachers' perceptions of students' engagement. The study concludes with recommendations for the Ministry of Education and EFL teachers and suggestions for further study.