Traditional methods of measurement of respiratory function in infants, such as whole body plethysmography, have been difficult to apply in clinical environments. Newer techniques for measuring lung mechanics, such as the use of forced exploratory flow-volume curves, can be easily used at the bedside and international standards are being produced to ensure maximum accuracy and reproducibility. Although continuous measurements obtained during tidal breathing are affected by many variables, there is increasing interest in the use of these bedside measurements of pulmonary function in clinical management and epidemiological studies.