This book explores the reasons why adult ESL learners drop out of their language classes, and suggests that those involved in ESL need to look beyond simplistic explanations to do with lack of time or interest. Based on a study of a group of Mexican immigrants to the US, the author proposes that superacin or 'self-actualization' is crucial to understanding the engagement and success (or failure) of adult ESL learners. Learners' decisions to drop out were not hasty or superficial but were based on a practical and in-depth assessment of the class, suggesting that those involved in delivering ESL to adult learners should stress the tangible, practical advantages that accrue with learning English, and at the same time strive to make instruction relevant and engaging.