The study aims to achieve three primary objectives: (1) To identify essential components for developing an instructional package aimed at enhancing English proficiency among individuals working in the Thai music industry; (2) To design an instructional package specifically tailored to improve the English proficiency of personnel in the Thai music industry; and (3) To implement the developed instructional package and assess its effectiveness in advancing English proficiency among music industry personnel. Employing the principles in developing an ESP course, the study comprises three phases: need analysis, instructional package development, and implementation. The need analysis phase involved surveying 150 individuals employed in the Thai music industry using a structured questionnaire. The instructional package development phase enlisted the expertise of five experts to evaluate the instructional model. Finally, phase three involved administering a pre-posttest study with 30 music professionals. The results highlight the successful creation of an English instructional package based on communicative language teaching (CLT) principles, leading to significant enhancements in participants' English proficiency. The study's significance lies in its identification of English language development needs within the music profession and its provision of a practical methodology for designing specialized English for Specific Purposes (ESP) courses tailored to the unique requirements of music professionals.