The CRMO/CNO workgroup aims to develop outcome measures to be used in all clinical trials with Chronic Nonbacterial Osteomyelitis (CNO) and Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis (SAPHO) syndrome patients. The initial step is to develop a core domain set (CDS), which can be used for studying the success of treatments in persons with a certain disease. A domain is a specific aspect of health that should be measured or monitored. There are some outcome measures developed but they did not include the essential input from patients and families. In this project, we plan to run focus groups and online discussion boards with CNO/SAPHO patients and their parents/caregivers to get their input on important aspects of their disease. The goal of this project is to develop a list of important factors to must be considered when developing outcome measurements for patients with CNO, specifically from the perspective of patients and caregivers.