ABSTRACT: BACKGROUND: This case report highlights the diagnostic and assessment difficulties faced by mental health professionals when dealing with a Deaf client. CASE PRESENTATION: We used mobile phone text facility to monitor and liaise with the client while in the community. We focused on the affect and signing amplitude/intensity of the client to make a diagnosis of bipolar disorder, prescribed valproate semisodium, and noticed an improvement in two months. CONCLUSION: This is an example of some areas of good practice when assessing a Deaf client with mental health problems.