Effective communication is essential to maintain mental health and resilience. Communication can be challenging for people who experience serious mental illness (SMI), which can be a barrier to social, employment and educational opportunities, as well as increasing their risk of experiencing abuse. Therefore, it is important that nurses who work with individuals experiencing SMI understand the assessment and management of specific communication, speech and language needs. This article focuses on five areas of communication, speech and language – receptive language, expressive language, speech, social communication and swallowing – to increase nurses’ confidence in assessing communication needs and making appropriate referrals to speech and language therapy services. The authors also suggest therapeutic interventions that nurses can use to reduce the effects of speech and language difficulties among people with SMI.