This study presents and tests a hypothesized structural model that attempts to explain the relationship of writing in English as a foreign language by Taiwanese university students to a variety of factors. Investigated were factors considered to be inhibiting (writing apprehension and writer's block), factors considered to be facilitative (free reading and self-initiated writing), and students' beliefs about and attitudes toward the instructional activities they experienced. Structural equation modeling was employed to test the interrelationships among the factors and the impact of each factor on writing performance. Results showed that free voluntary reading was the only significant predictor of writing performance. The analysis also confirmed that the modified model containing both facilitating and inhibiting factors was an adequate representation of the sample data.