The present study investigated temporal associations between putative emotion regulation strategies and negative affect in 20-month-old toddlers. Toddlers' parent-focused, self-distraction, and toy-focused strategies, as well as negative affect, were rated on a second-by-second basis during laboratory parent-toddler interactions. Longitudinal mixed-effects models were conducted to determine the degree to which behavioral strategy use predicts subsequent negative affect and negative affect predicts subsequent strategy use. Results with mother-toddler and father-toddler dyads indicated that parent-focused strategies with an unresponsive parent were followed by increases in negative affect, whereas toy-focused strategies were followed by decreases in negative affect. Results also indicated that toddler negative affect serves to regulate behavioral strategy use within both parent contexts. (Contains 1 footnote and 5 tables.)