CFTR modulators are a new class of medications that target the underlying defect in in cystic fibrosis (CF). Ivacaftor (IVA) and IVA combined with lumacaftor (IVA/LUM) have been approved by the FDA for use in CF patients. However, the FDA label for these medications encompasses patient groups that were not studied as part of the drug approval process. CF clinicians, patients, and their families have recognized a need for recommendations to guide the use of these medications.