This study examined the relationship between language competence and emotion regulation in children between the ages of 48 and 60 months. Thirty-one children who attended subsidized preschool programs serving children from low SES families participated, along with their primary caretaker. The children's receptive and expressive language competencies were assessed using the Preschool Language Scale. Emotion regulation was assessed using three distinct methodologies: (a) "parental report", with the Emotion Regulation Checklist; (b) "a narrative measure", the Macarthur Story Stem Battery; and (c) "observationally", the Transparent Box Task, a behavioral regulation assessment which is primarily non-verbal. Receptive and expressive language abilities were significantly, inversely correlated with a parent's report of their child's dysregulation. Expressive language, but not receptive language, was also significantly correlated with a parent's report of their child's positive emotional regulation. Both receptive and expressive language were significantly, positively correlated with a child's ability to tell positive, emotionally-resolved narratives. Similarly, the variables were inversely correlated with the use of aggressive themes in narratives. Of the two language competencies, only expressive language was found to have relationships with any prosocial themes in narratives. Expressive language was significantly, positively correlated with the use of verbal conflict resolution. There was a trend for expressive language to be positively correlated with the use of affliliative themes as well as themes of empathy/helping, however they did not reach statistical significance. With regards to the TBT, children had significantly higher expressive and receptive language could open the box, persist longer, conduct themselves in a regulated manner, and not show distractiblity. A child's ability to tell a coherent narrative was found to mediate the significant, inverse relationship between expressive language and dysregulation. There were no significant relationships found between a child's request for social support while completing the TBT with neither their language competence nor with any emotion regulation measures. There were also no significant findings between the amount of self-speech a child used and their receptive or expressive language competence nor with any measures of emotion regulation. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]