This review explores research over the past quarter century on couples with age differences. I present recent global trends in age-dissimilar couplings, illustrating a shift away from statistical marriage studies focusing on relationships' motivations, inequalities, and challenges, and largely underpinned by biological, economic, or demographic outlooks. Since the last review of age-dissimilar couples in 1993, there have been substantive qualitative developments. Scholarship looking beyond Euro-American contexts is increasingly common, as are approaches examining class, race, sexuality, culture, religion, and nationality, as well as age, marital status, education, and employment. This transformation informs new perspectives on power and partner choice. I argue that research now needs more fluid definitions of age differences, greater range in qualitative studies' geographies and methodologies, and continued consideration of the life course and intersecting differences. Examinations of age-dissimilar couples should thus focus on these relationships' varied configurations, explored through a range of social analyses.