Emotion is a basic phenomenon of human functioning, most of the time having an adaptive value enhancing our effectiveness in pursuing our goals in the broadest sense. Regulation of these emotions, however, is essential for adaptive functioning, and suboptimal or dysfunctional emotion regulation may even be counterproductive and result in adverse consequences, including a poor well-being and ill health. This volume provides a state-of-the art overview of issues related to the association between emotion regulation and both mental and physical well-being. It covers various areas of research highly relevant to both researchers in the field and clinicians working with emotion regulation issues in their practice. Included topics are arranged along four major areas: • (Neuro-)biological processes involved in the generation and regulation of emotions • Psychological processes and mechanisms related to the link between emotion regulation and psychological well-being as well as physical health • Social perspective on emotion regulation pertaining to well-being and social functioning across the life span • Clinical aspects of emotion regulation and specific mental and physical health problems This broad scope offers the possibility to include research findings and thought-provoking views of leading experts from different fields of research, such as cognitive neuroscience, clinical psychology, psychophysiology, social psychology, and psychiatry on specific topics such as nonconscious emotion regulation, emotional body language, self-control, rumination, mindfulness, social sharing, positive emotions, intergroup emotions, and attachment in their relation to well-being and health. Chapters are based on the “Fourth International Conference on the (Non) Expression of Emotions in Health and Disease” held at Tilburg University in October 2007. In 2007 Springer published “Emotion Regulation: Conceptual and Clinical Issues” based on the Third International Conference on the (Non) Expression of Emotion in Health and Disease,” held at Tilburg University in October 2003. It is anticipated that, depending on sales, we may continue to publish the advances deriving from this conference.