This paper reports the results of a case study of the strategies used by Arabic-speaking undergraduate simultaneous interpreter (SI) trainees while interpreting in booths under test conditions. The study was discourse-based as it adopted the main premise of the Information Processing approach to SI (Hodzik & Williams 2017, p. 2) which considers interpreting a language-dependent activity. The data consisted of a sample of the aforementioned trainees’ recorded interpretations of a video lecture on solar energy. The data analysis was based on Barik’s (1975, 2002) model of omission, addition and phrasing changes. The results show that the most frequent errors made and/or strategies used by the study subjects are delay omission and comprehension omission. This paper also presents a discourse-based module for SI training. The module is based on the premise that SI comprises an analysis of the comprehension phase of the source speech and the production phase of source speech messages in the target language. The material utilizes the main tenets of Setton’s (1993, 1998, 2002) model of comprehension and production and Seleskovitch’s (2008) model of teaching interpreting. This study thus sought to integrate research on SI into classroom practices.