The ability to regulate one's emotions is an integral part of human social behavior. One antecedent emotion regulation strategy, known as reappraisal, is characterized by cognitively evaluating an emotional stimulus to alter its emotional impact and one response-focused strategy, suppression, is aimed at reducing behavioral output. People are capable of using these specific emotion regulation strategies when instructed to do so; however, it is equally important to investigate natural and self-selected strategy use. This study was designed to determine to what extent people spontaneously regulate their emotions and the emotion regulation strategies they choose to achieve their regulatory goals. Participants were given no instructions to regulate their emotions before they were shown a negative and a positive film clip, but were instead asked afterwards about the specific strategies that they had used. Participants reported regulating their emotions more to the negative film than to the positive film. Reappraisal was more frequently selected as an emotion regulation strategy than suppression. As expected, participants with high baseline respiratory sinus arrhythmia (RSA) adopted reappraisal strategies more than those with low RSA but, surprisingly, RSA was not associated with facial expressivity. Suggestions for future research in this relatively young field of spontaneous emotion regulation are offered. (Contains 1 table and 1 figure.)