The main objective was to analyse the use of rigid laryngotracheoscopy under general anaesthesia (GA) and endoscopic surgery in the management of inspiratory stridor in patients referred to a paediatric ENT outpatient clinic. The secondary objective was to analyse the aetiological diagnoses made and their therapeutic management. This is a prospective study including all newborns and infants, corresponding to 190 patients, presenting for the first time in consultation for inspiratory stridor from January 2015 to December 2017. A consultation form was filled out after each consultation and added to a database; a management algorithm was used to determine which patients required a rigid laryngotracheoscopy. A 17.9% (n = 34) of the patients required rigid laryngotracheoscopy, of whom 12.6% (n = 24) underwent concomitant endoscopic surgery. A 65.8% (n = 125) of the patients were diagnosed with laryngomalacia, 21.1% (n = 40) with isolated posterior excess of mucosa, 9.5% (n = 18) with another diagnosis and 3.7% (n = 7) with a normal examination. The presence of comorbidity was associated (p < 0.001) with the use of rigid laryngotracheoscopy and endoscopic surgery.Conclusion: Rigid laryngotracheoscopy under GA was required in one in five to six patients. Conservative management with strict follow-up may be appropriate in a large number of patients, especially those with laryngomalacia. What is Known: • Previous research has established that laryngomalacia is the main aetiology of stridor. • Comorbidities are linked with a poor tolerance of stridor. What is new: • About one in five to six patients seen in consultation for stridor will require a trip to the operative room (and one in eight will require endoscopic surgery). • Laryngomalacia and isolated posterior excess of mucosa account for 85-90% of the patients seen in consultation for stridor.