Child maltreatment represents a significant public health, social welfare, and legal concern, with courts and statutory agencies increasingly relying on expert assessments to inform high-stakes decisions in child protection contexts. Despite this, practitioners lack consolidated, evidence-informed guidance on how to conduct such assessments, and existing guidance lacks the specificity required to meaningfully support them in this complex area. The present paper addresses this gap by presenting evidence-informed practice guidelines for forensic child maltreatment assessment, drawing on contemporary international research and principles of forensic psychological assessment. The guidelines address the full assessment process, including referral clarification, synthesis of collateral information, hypothesis generation, child interviews, caregiver-child observation, caregiver interviews, psychometric assessment, collateral interviews, risk assessment, formulation, and recommendations. Three distinct contributions are advanced: the introduction of behaviour chain analysis as a structured method for the functional assessment of maltreating behaviour; an extension of the 5P formulation model to incorporate prognosis; and a critical appraisal of the discriminative performance of available child maltreatment risk assessment instruments. These guidelines are intended to support, not replace, clinical expertise, and to promote consistency, transparency, and defensibility in professional practice across jurisdictions.