Inclusion Criteria:  Participants who are diagnosed with atopic dermatitis (AD). History of topical anti-inflammatory agents such as topical steroids and topical tacrolimus for AD. Participants initiating upadacitinib for the treatment of AD in routine clinical practice. Body weight >=30 kg at the start of dosing.  Exclusion Criteria:  Prior treatment with upadacitinib Currently participating in another registrational clinical research study Participants for whom upadacitinib is contraindicated