Despite recognition of a high prevalence of fatigue in individuals with chronic airflow obstruction conditions, including chronic obstructive pulmonary disease and asthma, and its importance from a quality of life perspective, no research was found in which fatigue was measured directly in these populations. This may be due to a seeming lack of appropriate instruments for measuring fatigue in these populations. The purpose of this study, therefore, was to pretest an instrument, the Piper Fatigue Scale, which was developed to measure chronic fatigue in clinical populations. The outpatient sample consisted of 17 persons with chronic obstructive pulmonary disease and 19 with asthma. Findings revealed that the visual analogue scale version of the Piper Fatigue Scale may not be appropriate for measuring fatigue in these populations. Instruments with validity and reliability for fatigue in chronic obstructive pulmonary disease and asthma need to be developed.