Psoriasis is a common immune-mediated skin disease producing significant morbidity. Tumour necrosis factor (TNF)-alpha, a pro-inflammatory cytokine, plays a key role in the cutaneous inflammation characteristic of psoriasis. Infliximab is a chimeric monoclonal antibody that specifically binds to TNF-alpha, thereby blocking its biological activity. Data from Phase II and III studies indicate that infliximab is a highly effective, rapidly acting systemic therapy for patients with moderate-to-severe psoriasis. Regular 8-weekly infusions of infliximab maintain significant clinical improvement in the majority of patients for at least 1 year. Infliximab is generally well tolerated, but patients may be susceptible to infection and malignancy.