Positive psychology interventions (PPIs) are evidence-based practices designed to enhance wellbeing by cultivating strengths, fostering gratitude, and promoting positive emotions. Developed primarily through research by Martin Seligman, Barbara Fredrickson, and others since the late 1990s, these interventions shift focus from fixing problems to building what's best in people. The PERMA model (Positive emotions, Engagement, Relationships, Meaning, Accomplishment) provides a foundational framework for understanding wellbeing dimensions. A crucial insight: research shows that person-activity fit—matching interventions to individual preferences, values, and strengths—significantly predicts effectiveness, meaning the "best" intervention is the one that resonates most with you personally and that you'll actually practice consistently.