Part I: Conceptual issues Overview of methods for adjustment and applications in the social and behavioral sciences: The role of study designTing-Hsuan Chang and Elizabeth A. Stuart Propensity scorePaul R. Rosenbaum Generalization and TransportabilityElizabeth Tipton and Erin Hartman Part II: Matching Optimization techniques in multivariate matchingPaul R. Rosenbaum and José R. Zubizarreta Optimal Full matchingMark M. Fredrickson and Ben Hansen Fine balance and its variations in modern optimal matchingSamuel D. Pimentel Matching with instrumental variablesMike Baiocchi and Hyunseung Kang Covariate Adjustment in Regression Discontinuity DesignsMatias D. Cattaneo, Luke Keele, Rocío Titiunik Risk Set MatchingBo Lu and Robert A. Greevy, Jr. Matching with Multilevel DataSamuel D. Pimentel and Luke Keele Effect Modification in Observational StudiesKwonsang Lee and Jesse Y. Hsu Optimal Nonbipartite MatchingRobert A. Greevy, Jr. and Bo Lu Matching Methods for Large Observational StudiesRuoqi Yu Part III: Weighting Overlap WeightingFan Li Covariate Balancing Propensity ScoreKosuke Imai and Yang Ning Balancing Weights for Causal InferenceEric R. Cohn, Eli Ben-Michael, Avi Feller, and José R. Zubizarreta Assessing Principal Causal Effects Using Principal Score MethodsAlessandra Mattei, Laura Forastiere, Fabrizia Mealli Incremental Causal Effects: An Introduction and ReviewMatteo Bonvini, Alec McClean, Zach Branson and Edward H. Kennedy Weighting Estimators for Causal MediationDonna L. Coffman, Megan S. Schuler, Trang Q. Nguyen, and Daniel F. McCaffrey Part IV: Machine Learning Adjustments Machine Learning for Causal InferenceJennifer Hill, George Perrett and Vincent Dorie Treatment Heterogeneity with Survival OutcomesYizhe Xu, Nikolaos Ignatiadis, Erik Sverdrup, Scott Fleming, Stefan Wager, Nigam Shah Why Machine Learning Cannot Ignore Maximum Likelihood EstimationMark J. van der Laan and Sherri Rose Bayesian Propensity Score methods and Related Approaches for Confounding Adjustment Joseph Antonelli Part V: Beyond Adjustments How to Be a Good Critic of an Observational StudyDylan S. Small Sensitivity AnalysisC.B. Fogarty Evidence FactorsBikram Karmakar