The 3-session Attachment and Biobehavioral Catch-up intervention (ABC 3) is a brief version of the standard protocol. Parents who receive ABC 3 will receive the first 3 sessions of the ABC intervention, which focus on enhancing parental sensitivity (i.e., nurturance to distress, following the child's lead) by providing in-the-moment feedback on parent-child interactions, video feedback, and discussion of manualized content. ABC 3 was adapted from the standard protocol based on modeling of session-by-session data that demonstrated that, on average, most of the change in parental sensitivity happens in the first several sessions of the intervention.

Safe Environment for Every Kid (SEEK) is an evidence-based screening and referral system to facilitate parents' access to services for risk factors for maltreatment, including: mental health, substance abuse, intimate partner violence, harsh parenting, major parental stress, and food insecurity. Parents first complete the SEEK Parent Questionnaire with the help of an outreach worker. Following the SEEK protocol, handouts will be provided that address the identified problems and parents will be referred to partnering organizations in the community. Any additional work is completed by phone. The developer of the intervention, Howard Dubowitz, is a consultant on this application and will provide support around effective implementation.

At 6 months post-intake, parental neural activity will be assessed using an event-related potential (ERP) task. Parents will categorize photographs of infants with different emotional expressions (crying, laughing, neutral), while continuous EEG is recorded (Bernard et al., 2015). The N170 (an early perceptual ERP component that indexes processing of faces) will be measured as the average amplitude within a time window of 140 to 180 ms at electrodes P7 and P8. After data processing (re-referencing, artifact rejection), residualized difference scores will be computed that reflect the magnitude of the difference in N170 responses to emotional faces versus neutral faces.

At 6 months post-intake, parental neural activity will be assessed using an event-related potential (ERP) task. Parents will categorize photographs of infants with different emotional expressions (crying, laughing, neutral), while continuous EEG is recorded (Bernard et al., 2015). The late positive potential (LPP; a late ERP component that indexes sustained attention and evaluation of emotionally-salient stimuli) will be measured as the average amplitude at the Pz electrode from 300 to 650 ms post-stimulus. After data processing (re-referencing, artifact rejection), residualized difference scores will be computed that reflect the magnitude of the difference in LPP responses to emotional faces versus neutral faces.

At 6 months post-intake, the Strange Situation procedure (Ainsworth et al., 1978) will be conducted. The Strange Situation consists of a series of episodes including two 3-minute separations, each followed by 3-minute reunions. The child's behavior upon reunion with the parent is coded for continuous scales (i.e., proximity seeking, contact maintenance, avoidance, resistance) and children are classified as secure, insecure-avoidant, or insecure-resistant. Following the Main & Solomon (1990) system, disorganized attachment behavior is also coded on a continuous scale, and children may receive a primary classification of disorganized attachment. Elizabeth Carlson, an expert coder, will serve as a consultant on this project and complete reliability coding for 25% of videos.

At 6 months post-intake, children's diurnal cortisol rhythms will be assessed. Cortisol is an end product of the hypothalamic-pituitary-adrenal (HPA) axis. The normative pattern is a high wake-up level, decreasing throughout the day, with the nadir in the evening. Parents will collect child saliva samples by rubbing an oral swab in the child's mouth at wake-up (morning) and bedtime (evening) for 3 consecutive days. Saliva samples will be assayed using the Salimetrics, Inc. High Sensitivity Salivary Cortisol Enzyme Immunoassay Kit. All samples from a child at a single time-point will be run in duplicate on the same assay plate, along with a control. Cortisol values, measured in ?g/dl, will be log-transformed. We will examine changes in the diurnal rhythm (i.e., slope) from wake-up to bedtime.

At 12 months post-intake, children's diurnal cortisol rhythms will be assessed. Cortisol is an end product of the hypothalamic-pituitary-adrenal (HPA) axis. The normative pattern is a high wake-up level, decreasing throughout the day, with the nadir in the evening. Parents will collect child saliva samples by rubbing an oral swab in the child's mouth at wake-up (morning) and bedtime (evening) for 3 consecutive days. Saliva samples will be assayed using the Salimetrics, Inc. High Sensitivity Salivary Cortisol Enzyme Immunoassay Kit. All samples from a child at a single time-point will be run in duplicate on the same assay plate, along with a control. Cortisol values, measured in ?g/dl, will be log-transformed. We will examine changes in the diurnal rhythm (i.e., slope) from wake-up to bedtime.

After ABC Session 3 (or the equivalent for SEEK-only dyads), parents will complete the Infant Externalizing Questionnaire (IEQ; Lorber et al., 2017) when children are 24 months of age or younger. The IEQ is a measure of infant aggression (7 items) and defiance (4 items) and shows good internal consistency, longitudinal stability, interparental agreement, and concurrent and predictive validity.

At 6 months post-intake, parents will complete the Infant Externalizing Questionnaire (IEQ; Lorber et al., 2017) when children are 24 months of age or younger. The IEQ is a measure of infant aggression (7 items) and defiance (4 items) and shows good internal consistency, longitudinal stability, interparental agreement, and concurrent and predictive validity.

At 12 months post-intake, parents will complete the Infant Externalizing Questionnaire (IEQ; Lorber et al., 2017) when children are 24 months of age or younger. The IEQ is a measure of infant aggression (7 items) and defiance (4 items) and shows good internal consistency, longitudinal stability, interparental agreement, and concurrent and predictive validity.

At 6 months post-intake, parents will complete the Child Behavior Checklist 1? - 5 (CBCL; Achenbach & Rescorla, 2001) for children at least 18 months old, which will allow us to assess both internalizing and externalizing behaviors. The use of the IEQ and the CBCL at overlapping waves of data collection is intentional because it allows us to correct for switching indicators in statistical analyses.

At 12 months post-intake, parents will complete the Child Behavior Checklist 1? - 5 (CBCL; Achenbach & Rescorla, 2001), which will allow us to assess both internalizing and externalizing behaviors. The use of the IEQ and the CBCL at overlapping waves of data collection is intentional because it allows us to correct for switching indicators in statistical analyses.

At the 6 months post-intake assessment, the Disruptive Behavior Diagnostic Observation Schedule (DB-DOS; Wakschlag et al., 2008) will be administered. The DB-DOS is an observational assessment that involves a series of "presses" that challenge children's emotional and behavioral regulatory capacities; the DB-DOS demonstrates good reliability and validity. Given that children will be between 12 and 30 months at the 6 months post-intake time-point, we will administer the infant/toddler DB-DOS protocol, which allows for the assessment of child irritability and frustration, key behavioral regulation constructs that are predictive of later difficulties with disruptive behavior disorders.

At 6 months post-intake, client satisfaction with services will be assessed with the Client Satisfaction Questionnaire (CSQ-8; Larson et al., 1979). The CSQ-8 is an 8-item questionnaire that asks participants about their satisfaction with services received (e.g., to what extent services met needs, likelihood of recommending a friend). The CSQ-8 provides a good measure of participants' perception of services received.

After ABC Session 3 (or the equivalent for SEEK-only dyads), we will assess subsequent reports of maltreatment to ACS, which will be coded as reported, investigated, and substantiated. In addition, we will code available records using the Modified Maltreatment Classification System (Barnett et al., 1993) for type and severity of maltreatment exposure.

At 6 months post-intake, we will assess subsequent reports of maltreatment to ACS, which will be coded as reported, investigated, and substantiated. In addition, we will code available records using the Modified Maltreatment Classification System (Barnett et al., 1993) for type and severity of maltreatment exposure.

At 12 months post-intake, we will assess subsequent reports of maltreatment to ACS, which will be coded as reported, investigated, and substantiated. In addition, we will code available records using the Modified Maltreatment Classification System (Barnett et al., 1993) for type and severity of maltreatment exposure.