Given the powerful implications of relationship quality for health and well-being, a central mission of relationship science is explaining why some romantic relationships thrive more than others. This large-scale project used machine learning (i.e., Random Forests) to 1) quantify the extent to which relationship quality is predictable and 2) identify which constructs reliably predict relationship quality. Across 43 dyadic longitudinal datasets from 29 laboratories, the top relationship-specific predictors of relationship quality were perceived-partner commitment, appreciation, sexual satisfaction, perceived-partner satisfaction, and conflict. The top individual-difference predictors were life satisfaction, negative affect, depression, attachment avoidance, and attachment anxiety. Overall, relationship-specific variables predicted up to 45% of variance at baseline, and up to 18% of variance at the end of each study. Individual differences also performed well (21% and 12%, respectively). Actor-reported variables (i.e., own relationship-specific and individual-difference variables) predicted two to four times more variance than partner-reported variables (i.e., the partner’s ratings on those variables). Importantly, individual differences and partner reports had no predictive effects beyond actor-reported relationship-specific variables alone. These findings imply that the sum of all individual differences and partner experiences exert their influence on relationship quality via a person’s own relationship-specific experiences, and effects due to moderation by individual differences and moderation by partner-reports may be quite small. Finally, relationship-quality change (i.e., increases or decreases in relationship quality over the course of a study) was largely unpredictable from any combination of self-report variables. This collective effort should guide future models of relationships.

Friends with benefits relationships (FWBRs) uniquely combine friendship with sexual activity but differ from romantic relationships in that they may be less likely to be exclusive or long lasting. A longitudinal analysis of the trajectory of FWBRs is presented, in which participants in FWBRs at Time 1 reported on their relationship outcomes at Time 2 (N = 192). Results demonstrated that a plurality of FWBRs transitioned into having no relationship of any kind at Time 2 (31%). Those who wanted their FWBR to transition into a friendship typically obtained that outcome (59%), whereas those who wanted to transition into a romantic relationship did not (15%). Time 2 relationship status predictors and further implications of FWBR trajectories are discussed.

Does believing in torture's effectiveness shape the endorsements of its use? Using a multimethod approach across six studies, we provide converging evidence that efficacy beliefs can help increase understanding of individual differences and situational influences on torture support. Studies 1a and 1b found that torture opinions contained more efficacy-based language than other types of harm and that people relied more on torture efficacy than torture's inherent morality when conveying their views. Study 2 assessed predictors of torture favorability including effectiveness and other key covariates, revealing that efficacy beliefs strongly predicted torture favorability-an association that retained its predictive validity above and beyond individual differences known to influence torture support. Mediation analyses further showed that efficacy beliefs explained key associations with torture support. Studies 3 and 4 used moral dilemmas requiring decisions about torture versus other harm. Results showed that individuals who believed harm would be effective were more likely to endorse its use; this was especially evident for torture judgments. Study 5 replicated the torture-efficacy effect while also revealing efficacy effects for other interrogation techniques, thus suggesting the effect is driven more by the instrumental objective of torture than harm or moral violations. Theoretical and practical implications are discussed.

Across three studies (total N = 993) with diverse methodologies (i.e., experimental studies, longitudinal in vivo sampling), we found that there are distinct reasons why individuals believe their romantic relationship will become, or did become, less committed, and reasons why individuals believe their relationships will become, or became, more committed. Whereas the strongest endorsed reasons to stay (e.g., satisfaction) are the same as the strongest endorsed reasons to leave (e.g., dissatisfaction), there are many constructs that are more strongly endorsed as either leave reasons (e.g., quality of alternatives) or stay reasons (e.g., love). These reasons are important glimpses into the process that occurs when someone is deciding whether to stay or leave a relationship, and results empirically confirm a core tenet of Interdependence Theory that until now has been only theoretical (i.e., some outcomes contribute more motivation to staying in the current relationship, whereas others contribute more motivation to leaving).

The dissolution of romantic relationships can be conceptualized in many ways, from a distressing event or a consequential life decision to a metric of a relationship's success. In the current review, we assess how relationship science has approached dissolution research over roughly the past 20 years. We identified 207 studies (from 195 papers) published between 2002–2020 that captured relationship dissolution events and coded the papers for relevant features. The most common methodological approach to studying breakups was a self‐report study (92%) in which relationships were tracked over time (72%) and breakups were treated as an outcome variable (79%). These results suggest that most research on dissolution has focused on predictors of it, rather than processes required to uncouple and circumstances surrounding the breakup itself. Coding revealed heterogeneous theoretical approaches, with the most common perspective across papers—social exchange/interdependence theory—informing only 15% of the papers coded. A majority (61%) of samples were representative of the nations, regions, or localities in which the studies were conducted. Yet, samples still tended to be disproportionately comprised of young, white individuals from Western countries. We conclude by discussing potential avenues for moving our understanding of relationship dissolution forward.