For decades, social psychological theories have posited that the automatic processes captured by implicit measures have implications for social outcomes. Yet few studies have demonstrated any long-term implications of automatic processes, and some scholars have begun to question the relevance and even the validity of these theories. At baseline of our longitudinal study, 135 newlywed couples (270 individuals) completed an explicit measure of their conscious attitudes toward their relationship and an implicit measure of their automatic attitudes toward their partner. They then reported their marital satisfaction every 6 months for the next 4 years. We found no correlation between spouses' automatic and conscious attitudes, which suggests that spouses were unaware of their automatic attitudes. Further, spouses' automatic attitudes, not their conscious ones, predicted changes in their marital satisfaction, such that spouses with more positive automatic attitudes were less likely to experience declines in marital satisfaction over time.