Recognizing the importance of students' attitudes in enhancing their academic achievements, this qualitative study aimed to examine the role of second language (L2) willingness to communicate (WTC) in students' English language achievements. The data were collected through semi-structured face-to-face interviews with 11 Afghan English as a Foreign Language (EFL) university instructors. The data was analyzed thematically, with findings being divided into major and sub-themes. The results revealed a positive relationship between students' willingness to communicate and their language achievements. The effective strategies for promoting students' WTC, as identified by the interviewed participants, were discussed. Specifically, the findings indicated that group work activities, exposure to authentic teaching materials, understanding students' needs and wants, creating a comfortable learning environment, listening to and respecting students' ideas, and acknowledging their achievements all contribute to promoting students' WTC. Furthermore, the findings revealed that instructors struggle with challenges such as a lack of instructional resources, multi-level and large classes, which constrains teachers' ability to implement activities to enhance students' willingness to communicate in the English language. The discussion includes further analysis of the findings, recommendations, and suggestions for future research directions.