Research supports an association between children’s communication needs and their social, emotional and mental health (SEMH). Vulnerable populations of children and adolescents have a higher than expected prevalence of communication needs. Importantly, these communication needs are not consistently identified nor addressed. In response to this, the profession of speech and language therapy advocates the involvement of speech and language therapists in health, education, and social services to accurately assess the communication needs of these children and young people and to provide evidence-based interventions to facilitate more effective communication between the child, their family and professionals. This chapter discusses the research identifying the communication needs of these vulnerable children and young people. The role of the speech and language therapist is explained and specific approaches that all professionals can adopt to enable effective communication advocated. Case examples of children will be used to illustrate the profiles of communication needs and how communication interventions can address these.