With a collaboration among Language Institute Thammasat University faculty members and a textbook writing grant from the Language Institute Thammasat University, this textbook Developing Effective Paragraph Writing Skills is intended as a text for a course in English writing at tertiary level. It is designed to help Thai EFL learners from different disciplines improve their academic writing skills which are essential for their higher education. It offers an outline account of the most important and central writing constructions in English. With clear step-by-step instructions in paragraph writing, Developing Effective Paragraph Writing Skills builds writing, reading, and critical thinking skills, and also combines comprehensive grammar review with an introduction to writing. Constant reinforcement is provided through examples and exercises.