Language learning is a great fascination, especially the learning of a Foreign and or Second Language. Numerous studies have been carried out to establish factors that hinder and or promote language learning, among them First Language interference. The debate on Mother Tongue interference seem to have tied out, but this work rekindles it with a view of rethinking and understanding the role of Mother Tongue in learning English as a Second Language. This book presents findings on a study on First Language transfer and its implication on the teaching and learning of English as a Second Language. The study found out, among other issues, that the knowledge and structure of the First Language ought to foster the learning of the Second language. Language teachers ought to understand this in order to structure their lesson preparation and presentation. It is a must read for both teachers and students of English as a Second Language, as well as language course & learning material developers.