The Gratitude Questionnaire six-item form (GQ-6) was developed to measure dispositional gratitude. The scale contains six items that assess four separate but co-occurring components contributing to the experience of gratitude: frequency, intensity, span and density, which are rated on a 7-point Likert scale. This chapter offers a concise overview of the theoretical principles of gratitude, initial scale development, and validation. An account of subsequent studies reviewing psychometric properties is presented, followed by a recent Rasch analysis summary, including an ordinal-to-interval conversion table, demonstrating the scale’s reliability and precise measurement qualities. Results from studies utilizing the GQ-6 are explored, as well as the influence that language and culture have on the GQ6, followed by a review of translated versions and the scale’s limitations. The GQ-6 is the most widely used measurement tool for assessing gratitude. Additionally, mindfulness practices often incorporate the cultivation of gratitude, making the GQ-6 a relevant tool for mindfulness researchers. With growing empirical evidence and robust psychometric properties, the scale offers researchers and practitioners a brief, suitable measure of dispositional gratitude. However, more research is needed to validate these findings within clinical populations.