Complexity, accuracy, and fluency (CAF) are measures of language proficiency in productive skills. This study with a non-equivalent control group pretest-post-test design explored whether Dynamic Assessment (DA) procedures enhances EFL teachers' writing CAF. Three 22-member groups of homogeneous teachers were randomly assigned to one control group (Non-DA), an interactionist DA group (IA-DAG), and an interventionist DA group (IV-DAG). After the nine-session treatment, the study groups took a writing post-test. A one-way ANOVA test showed that the experimental groups outperformed the control group, although no significant differences were found between DA groups. Besides, no statistically significant differences were found between the groups' writing complexity. Considering accuracy, IA-DAG outperformed Non-DAG whereas no significant differences were observed between the experimental groups and between IV-DAG and Non-DAG. Fluency measures showed the superiority of DA groups to the control group. The first conclusion was that DA processes have a decisive role in improving writing skills and the CAF triad. Second, CAF components do not develop in a linear process, and employing DA procedures can be useful for its improvement. The paper has implications for language teachers and SLA researchers.
