Dasypus novemcinctus (Nine-banded Armadillo) produces litters of genetically identical quadruplets and, because of this, has long been considered a potential model system for the study of kin selection. However, long-term field studies have failed to reveal any obvious instances of kin-selected altruism in this species. Social interactions, such as altruism, require time and energy. The time-constraints hypothesis proposes that, because of certain aspects of their biology, Nine-banded Armadillos may have to devote most of their active time to foraging, thus precluding any opportunity for the evolution of kin-selected social behavior. To determine the potential validity of this conjecture, we recorded time budgets of wild Nine-banded Armadillos at a study site in western Mississippi during two summers. Both focal and instantaneous sampling showed armadillos allocated 77–90% of their above-ground active time to foraging. A search of the literature indicated that this is among the highest values reported for any mammal. We interpret these findings as consistent with the time-constraints hypothesis.