Interpersonal emotion regulation shapes people's emotional and relational experiences. Yet, researchers know little about the regulation processes that influence these outcomes. Recent works in the intrapersonal emotion regulation space suggest that motivational strength, or effort, people invest in regulation might be the answer. We applied this motivated approach for the first time in the interpersonal space-looking at both intrinsic and extrinsic forms of interpersonal emotion regulation-in order to identify the potential emotional and relational outcomes of putting effort into regulating one's own emotions through others, and regulating others' emotions. In daily diary (N = 171) and experience sampling (N = 239) studies, we examined participants' interpersonal emotion regulation behaviors and socioemotional experiences in everyday social interactions over the course of 1 week. These methods allowed us to examine effort at both momentary and person levels. We found that people who habitually put in more intrinsic effort to feel better through others felt worse overall. People also felt worse on occasions when they put in more effort to extrinsically help others feel better, although at the person level extrinsic effort was associated with higher interaction quality. Together, our findings suggest that interpersonal emotion regulation success is not simply a matter of trying hard. This observation opens new research avenues to investigate the interplay of different factors that determine when, and for whom, investing effort in interpersonal emotion regulation pays off. (PsycInfo Database Record (c) 2024 APA, all rights reserved).