This study investigated the response of two cultivars of lowbush blueberries, Vaccinium angustifolium Ait., cultivars Fundy and Blomidon, to controlled atmosphere (CA) storage in all combinations of 1, 2, and 5% O2 and 0, 5, 10, and 15% CO2, and storage in air. A second set of samples was inoculated with a Botrytis-infected raspberry prior to storage to determine the effect of CA storage on decay development. The berries were held at 0 °C in air-tight chambers flushed each day for 30 min. Half-liter samples were stored for 2,4, and 6 wk in air or CA storage and then evaluated for percent unmarketable berries, firmness, titratable acids and percent decayed berries. This was followed by 7 d in air at 10 or 20 °C and recording of percent unmarketable berries. The experiment was replicated over 2 yr. Both cultivars responded positively to CA storage. Increasing CO2 in the presence of 1–5% O2 reduced decay and the percent unmarketable berries and maintained titratable acids and berry firmness levels. After 42 d of storage, Fundy had 30.5% unmarketable berries in air storage, compared with 8.7% in 15% CO2. Blomidon had 36.0% and 6.8% unmarketable berries in air and 15% CO2, respectively. Decreasing O2 reduced the percentage decayed berries and maintained titratable acids. Botrytis inoculation before storage reduced berry quality, but cultivars responded differently. The quality of berries 7 d after removal from storage was influenced primarily by cultivar, storage time and shelf temperature and not by storage atmosphere. Key words:Vaccinium angustifolium, oxygen, carbon dioxide, shelf-life, firmness, titratable acidity, decay, CA storage