For decades, teachers and researchers in the areas of linguistics and education have wondered what makes skillful or successful learners different from less skillful or less successful ones. Even though a number of factors intervene in the teaching-learning process, it has been shown that what makes a difference in the students’ performance is the effective use of learning strategies. In the area of writing in particular, the appropriate and conscious employment of metacognitive strategies has proved to be beneficial in enhancing self-directed and autonomous learning, and also, in some cases, in improving students’ writing performance. This book offers teachers of language and of other areas and secondary and university students the theoretical underpinnings supporting the teaching and deployment of metacognitive writing strategies (MWS) and a model for the instruction of the MWS of planning, monitoring and evaluating, along with material and activities that have been used in the instruction of MWS in an English Teacher Training College in an Argentinian university, which could be adapted to any educational context and age group.