The social organization of a colony of the ant Myrmica sabuleti is defined. This colony contained six different kinds of workers differing in their linear speed, angular speed, orientation, audacity, tactile perception, aggressiveness, escaping ability, conditioning acquisition, activity, and brood caring. For each kind of ants, two ants were examined. The different kinds of ants differed in their examined biological traits. Also, the two workers of each kind slightly differed with respect to their biological traits from one another: the workers located far from the nest differing more than the workers located near or in the nest. Some cases of idiosyncrasy could be revealed. These findings are in agreement with what is generally reported about the ant colony organization, but are more precise, and more informative. The organization found herein is valid for the examined colony, at a given time, and could change over the seasons, be different for other colonies, and of course differs from that of other ant species.