Positive behavior interventions and supports (PBIS) is a three-tiered framework shown to improve student behavioral outcomes. There has been considerable investment in scaling up Tier 1 PBIS but less focus on scaling Tier 2 supports. Having greater insight into teachers,' students,' and families' perceptions regarding the social validity of Tier 2 interventions may further facilitate the scale-up of this more resource-intensive level of the multitiered model. The primary objective of this systematic literature review was to evaluate the social validity of Tier 2 interventions in 48 experimental studies, 65% of which systematically assessed social validity. Almost all studies reporting social validity data surveyed student participants and teachers (94%). Results indicated teachers and students primarily reported positive perceptions regarding Tier 2 interventions, although some teachers expressed concerns with effectiveness of the outcomes. Findings provide insights that can help promote the scale-up and broader dissemination of Tier 2 supports.