We developed a new method to link designer emotions with corresponding designer activities while using computer-aided design (cad) software. Our method employs automated facial emotion detection software and cursor tracking. We applied this method via an experiment with nine participants, each working with the same synchronously collaborative cad platform, and assigned a series of cad tasks in one of two distinct working styles: single participants working by themselves and paired participants working together. We analyzed and compared trends in emotion for these two working styles. Pairs, on average per person, experienced higher levels of emotion (measured as joy, sadness, anger, contempt, fear, and surprise) than individuals. We linked occurrences of each emotional response to their antecedent activities in the cad environment (navigating the model tree, sketching in the graphics area, making selections in the feature menu, and communicating using the chat window). Using a logistic regression analysis, we revealed statistically significant trends linking emotions and cad events, and we found that some emotions are more likely to occur with certain designer actions in the cad software. The method and conclusions presented in this paper allow us to better understand designer emotions in traditional and collaborative cad, which link to the established relationships between emotion and designer satisfaction, creativity, performance, and other outcomes increasingly valued by engineering designers and managers in virtually collaborative environments.