ABSTRACT:
This study aimed to investigate the effects of task-induced involvement load on the L2 incidental vocabulary acquisition  hrough  reading. The study made use of the experimental method to meet such an end. A number of instruments for fulfilling the research main purpose were utilized, namely Oxford placement test, and the vocabulary size test, and Wesche & Paribakht's (1996) Vocabulary Knowledge Scale. Descriptive statistics were employed to explore the statistical differences between the groups. Once this difference was shown to exist, inferential statistics were used to explain whether differences were significant or not. One-way ANOVA followed by Bonferroni post-hoc test was carried out to compare groups. The participants were 45 pre-intermediate ESL students in the preparatory year in King Saud University.  The results of the study revealed that task-induced involvement has considerable gains in developing vocabulary acquisition and retention across the three administered tasks. The study concluded with a number of pedagogical implications and suggestions for further research.