He works with adults and adolescents and their families. He has an interest in treating depression, anxiety disorders, adjustment disorders, behavioural difficulties, sexual paraphilias and inappropriate sexual behaviours. He works collaboratively with his clients using a range of evidence-based approaches including Cognitive Behavioural Therapy (CBT) and occasionally drawing on frameworks from Acceptance and Commitment Therapy (ACT), schema therapy, mindfulness, and hypnotherapy if required. Renn is open to conducting therapy sessions in Malay, Cantonese or Mandarin if required. Renn is a member of the Australian Psychological Society and British Psychological Society.