This study examines the change that occurs over the course of long-term marriages as well as thematic analysis of factors that contributed to the success of respondents’ marriages. A self-report short-form marital assessment was given to each spouse in long-lasting marriages to ask how aspects of the relationship have changed over time. An expanded group of couples in 50+ year marriages were asked an open-ended question about what has made their marriage successful. Quantitative analysis reveals statistically significant differences over time, while thematic analysis reveals 4 key themes in the responses about marital success.