Motivation in English for Specific Purposes (ESP) courses is an issue of utmost importance. Expanding specialized vocabulary is one of the objectives defined by ESP stakeholders. Therefore, the aim of this study was to investigate the role of vocabulary enrichment through close integration of reading and writing tasks in promoting advanced English for Occupational Purposes (EOP) learners’ motivation and attitudes. To this end, fifteen civil engineers were selected through convenience sampling. Following an eight-session course centered around technical vocabulary using reading and writing tasks, questionnaires were used as pretest and posttest based on Attitudinal/Motivation Test Battery (ATMTB), to measure nine types of motivation. Nine paired samples t-tests were conducted to determine whether there was a mean difference in the questionnaire results across time from pretest to posttest. The results demonstrated significant increase in all types of motivation following the integration of reading and writing tasks, excluding intrinsic motivation considering self-confidence. It was shown that there is a close relation between ESP learners’ motivation and the amount of vocabulary they learn. The results proposed certain practical strategies in order for ESP/EOP material developers and teachers to fulfill the objectives and aims of these needs-based courses.
