Inclusion Criteria:  Confirmed diagnosis of moderate to severe chronic plaque-type psoriasis diagnosed by a specialist t at the time of recruitment. Initiating an approved biologic treatment for psoriasis as per regulatory and reimbursement policy in Taiwan. Physician's decision with any of the above-mentioned treatments must have been reached prior to and independently of recruitment in the study. Treatments prescribed in accordance to both the product monograph, regulatory and reimbursement policies in Taiwan.  Exclusion Criteria:  - Participation in an interventional clinical trial, concurrently or within the last 30 days. Participation in another PMOS or Registry is acceptable.