Download PDF *Please see PDF for any images. Abstract This qualitative embedded case study aims to examine how applying multimedia theories in online courses can enhance vocabulary acquisition, retention, and production among adult English as a Second Language (ESL) learners at a non-profit organization in Ontario, Canada. Guided by Mayer’s Cognitive Theory of Multimedia Learning (CTML), the study probes how ESL learners can transfer, retain, and produce new vocabulary more effectively. D...| Contact