This book presents the findings of a small-scale classroom research carried out to investigate the effect of written error correction feedback on undergraduates ESL writings. Although effective writing skills are significant to the success of university students, second language (L2) writers face challenges in developing writing skills. The ability to produce linguistically accurate writing need to be developed among undergraduates. However, due to their grammatical inaccuracies, many of the writings are difficult to understand. Thus this study was designed to investigate a suitable feedback technique to improve these students L2 writing. There has been a longstanding controversy in the L2 literature regarding the effectiveness of error correction . Hence this study attempted to find out the effect direct error correction feedback and indirect error correction feedback had on students' writing.