Issue Information. Editorial: 'The early bird catches the worm'-the need for even earlier intervention and targeted prevention for mental illnesses. Issue Information. Editorial: Standardizing methods and measures in randomized controlled trials: a necessary catalyst for clinical translation. Issue Information. Editorial: Is child mental health research structurally racist? Issue Information. "School of hard knocks" - what can mental health researchers learn from the COVID-19 crisis? Annual Research Review: Anterior Modifiers in the Emergence of Neurodevelopmental Disorders (AMEND)-a systems neuroscience approach to common developmental disorders. Associations between physiological and neural measures of sensory reactivity in youth with autism. Prospective impact of COVID-19 on mental health functioning in adolescents with and without ADHD: protective role of emotion regulation abilities. Developmental differences in neural connectivity for semantic processing in youths with autism. Practitioner Review: Parenting interventions for child conduct problems: reconceptualising resistance to change. Adaptive intervention for prevention of adolescent suicidal behavior after hospitalization: a pilot sequential multiple assignment randomized trial. Moderators of response to child-based and parent-based child anxiety treatment: a machine learning-based analysis. Executive function mediates the prospective association between neurostructural differences within the central executive network and anti-social behavior after childhood traumatic brain injury. Childhood psychopathology mediates associations between childhood adversities and multiple health risk behaviours in adolescence: analysis using the ALSPAC birth cohort. Commentary: Does 'cry it out' really have no adverse effects on attachment? Reflections on Bilgin and Wolke (2020). No evidence for a core deficit in developmental dyscalculia or mathematical learning disabilities. Commentary: On intimate relationships, adult roles, interplay of family adversity and individual vulnerability, intergenerational transmission, and developmental selection - commentary on Vergunst et al. (2020). Immersive virtual reality and digital applied gaming interventions for the treatment of mental health problems in children and young people: the need for rigorous treatment development and clinical evaluation. Examining the bidirectional association between emotion recognition and social autistic traits using observational and genetic analyses. A scalable computational approach to assessing response to name in toddlers with autism. Impact of language disorders on children's everyday lives from 4 to 13 years: Commentary on Le, Mensah, Eadie, McKean, Schiberras, Bavin, Reilly and Gold (2020). Does maternal psychopathology bias reports of offspring symptoms? A study using moderated non-linear factor analysis. What does genetic research tell us about the origins of language and literacy development? A reflection on Verhoef et al. (2020). Commentary: Social Immune Processes as Pathways to Psychopathology: a commentary on Robles (2020). Brain activity during facial processing in autism spectrum disorder: an activation likelihood estimation (ALE) meta-analysis of neuroimaging studies. Identifying environmental pathways between irritability during childhood and suicidal ideation and attempt in adolescence: findings from a 20-year population-based study. Differential outcomes of tonic and phasic irritability in adolescent girls. Depicting the composition of gut microbiota in children with tic disorders: an exploratory study. Analysis of structural brain asymmetries in attention-deficit/hyperactivity disorder in 39 datasets. Commentary: Meeting the challenge of multidimensionality in neurodevelopmental disorders-reflections on Johnson et al. (2021). Impact of attention-deficit/hyperactivity disorder comorbidity on longitudinal course in Internet gaming disorder: a 3-year clinical cohort study. Joint engagement is a potential mechanism leading to increased initiations of joint attention and downstream effects on language: JASPER early intervention for children with ASD. Early language screening and intervention can be delivered successfully at scale: evidence from a cluster randomized controlled trial. Commentary: "Harvest for the World": Working locally to grow autism services globally - reflections on Divan et al. (2021). Symptom trajectories in the first 18 months and autism risk in a prospective high-risk cohort. Polygenic risk for depression, anxiety and neuroticism are associated with the severity and rate of change in depressive symptoms across adolescence. Effects of methylphenidate on executive functioning in children and adolescents with ADHD after long-term use: a randomized, placebo-controlled discontinuation study. Characterizing neuroanatomic heterogeneity in people with and without ADHD based on subcortical brain volumes. Reducing depression-related stigma and increasing treatment seeking among adolescents: randomized controlled trial of a brief video intervention. The role of child negative emotionality in parenting and child adjustment: Gene-environment interplay. Commentary: Reducing youth firearm violence and the associated health disparities requires enhanced surveillance and modern behavioral intervention strategies - a commentary on Bottiani et al. (2021). Online-delivered parenting intervention for young children with disruptive behavior problems: a noninferiority trial focused on child and parent outcomes. Diagnostic shifts in autism spectrum disorder can be linked to the fuzzy nature of the diagnostic boundary: a data-driven approach. The predictive capacity of psychiatric and psychological polygenic risk scores for distinguishing cases in a child and adolescent psychiatric sample from controls. Issue Information. Editorial: Biomarkers in precision medicine for mental illnesses. Issue Information.