Background: Air-liquid interface cultures using murine tracheal respiratory epithelium have revolutionized the in vitro study of airway diseases. However, these cultures often are impractical because of the small number of respiratory epithelial cells that can be isolated from the mouse trachea. The ability to study ciliary physiology in vitro is of utmost importance in the research of chronic rhinosinusitis (CRS). Our hypothesis is that the murine nasal septum is a better source of ciliated respiratory epithelium to develop respiratory epithelial air-liquid interface models. Methods: Nasal septa and tracheas were harvested from 10 BALB/c mice. The nasal septa were harvested by using a simple and straightforward novel technique. Scanning electron microscopy was performed on all specimens. Cell counts of ciliated respiratory epithelial cells were performed at one standard magnification (1535X). Comparative analysis of proximal and distal trachea, midanterior and midposterior nasal septal epithelium, was performed. Results: Independent cell counts revealed highly significant differences in the proportion of cell populations (p < 0.00001). Ciliated cell counts for the trachea (106.9 ± 28) were an average of 38.7% of the total cell population. Nasal septal ciliated epithelial cells (277.5 ± 16) comprised 90.1% of the total cell population. Conclusion: To increase the yield of respiratory epithelial cells harvested from mice, we have found that the nasal septum is afar superior source when compared with the trachea. The greater surface area and increased concentration of ciliated epithelial cells has the potential to provide an eightfold increase in epithelial cells for the development of air-liquid interface cultures. Copyright © 2007, OceanSide Publications, Inc.