Emotion is a “double-edged sword” that can either enhance or hinder various aspects of our cognition and behavior. For instance, the emotional charge of an event can increase attention to and memory for that event, whereas task-irrelevant emotional information may lead to increased distraction away from goal-relevant tasks. Sometimes, even the same emotionally arousal event can lead to opposite effects on different aspects of cognitive processing—hearing a gunshot might enhance memory for central aspects of what was happening at the time, while impairing memory for peripheral details. Stress can also lead to quite different effects depending on the context and degree of stress. For example, emotional responses associated with optimal levels of stress (eustress) may increase performance (e.g., positive emotions associated with wedding preparations), whereas emotions associated with exposure to extreme levels of stress impair performance (e.g., overwhelming worry in the anticipation of a difficult exam). Importantly, these effects are also susceptible to cognitive influences, typically exerted in the form of emotion control, which may affect both the immediate and the long-term impact of emotion on cognition. Although during the last decades important progress has been made in understanding emotion-cognition interactions, a number of aspects remain unclear. The present e-book and research topic comprise a collection of manuscripts discussing emerging evidence regarding the mechanisms underlying emotion-cognition interactions in healthy functioning and alterations associated with clinical conditions, in which such interactions are dysfunctional. Co-hosted by the Frontiers in Neuroscience—Integrative Neuroscience and Frontiers in Psychology—Emotion Science, our special research topic attracted a large number of outstanding contributions, based on approaches spanning from behavioral and lesion to pharmacological and brain imaging, and including empirical, theoretical, and review papers alike. The contributions are grouped around the following seven main themes distributed across the two hosting journals: (1) Emotion and Selectivity in Attention and Memory, (2) The Impact of Emotional Distraction; Linking Enhancing and Impairing Effects of Emotion, (3) What Really is the Role of the Amygdala?, (4) Age Differences in Emotion Processing; The Role of Emotional Valence, (5) Affective Face Processing, Social Cognition, and Personality Neuroscience, (6) Stress, Mood, Emotion, and the Prefrontal Cortex; The Role of Control in the Stress Response, (7) Emotion-Cognition Interactions in Clinical Conditions. This comprehensive approach allowed an integrative understanding of the available evidence and identification of concrete venues for future investigations.