The authors of the article respond to I. García-Talavera's reaction to their trial on ambulatory oxygen (AO) in oxygen-dependent chronic obstructive pulmonary disease (COPD). They acknowledge that their findings, which showed no improvement in quality of life or walking distance with as-needed AO for 3 months, contradict current guidelines. The authors attribute the negative results to the small sample size, suggesting that repeated trials would likely yield similar outcomes. They also address concerns about variations in oxygen saturation and mean arterial oxygen tension during the 6-minute walk test, noting that these values reflect the trial's inclusion criteria. The authors conclude that while a small proportion of patients with oxygen-dependent COPD might benefit from AO, identifying these patients is challenging, and acute responses do not predict long-term improvements in quality of life.The authors of the article respond to I. García-Talavera's reaction to their trial on ambulatory oxygen (AO) in oxygen-dependent chronic obstructive pulmonary disease (COPD). They acknowledge that their findings, which showed no improvement in quality of life or walking distance with as-needed AO for 3 months, contradict current guidelines. The authors attribute the negative results to the small sample size, suggesting that repeated trials would likely yield similar outcomes. They also address concerns about variations in oxygen saturation and mean arterial oxygen tension during the 6-minute walk test, noting that these values reflect the trial's inclusion criteria. The authors conclude that while a small proportion of patients with oxygen-dependent COPD might benefit from AO, identifying these patients is challenging, and acute responses do not predict long-term improvements in quality of life.