In the digital era, university instructors working in English for Technical Sciences (ETS) have opportunities, some might say obligations, to use audio-visual resources to motivate students. Such materials also call on cognitive and constructivist mechanisms thought to improve uptake of the target language (Tarnopolsky, 2012). This chapter reports on a small-scale study on the effectiveness of audio-visual materials in the development of comprehension and vocabulary skills in ETS. The study was conducted at the College of Applied Technical Sciences in Serbia and involved three groups of students: an audio-visual group exposed only to the video resources, a control group using web print-outs, and a combined group with access to both types of materials. Student performance was compared, and evaluation questionnaires developed to collect feedback from all participants. This chapter details the entire process of the study, elaborates on the findings, and gives an analysis of the data obtained to advocate for a more extensive use of audio-visual material in ETS practice. [For the complete book, "New Developments in ESP Teaching and Learning Research," see ED578581.]