There is an increasing literature on the pathological and clinical significance of “inflammatory” biomarkers in asthma and chronic obstructive pulmonary disease (COPD). Their potential role includes risk assessment, but this is somewhat different for the two conditions. In asthma the aim is to identify future risk of poor asthma control or exacerbations. Although induced sputum eosinophils and exhaled nitric oxide are the most widely investigated candidates for use in the clinical arena, there is scope for a great deal of improvement in their application and other biomarkers may prove to be better. For COPD, risk assessment is somewhat different. There is the potential to use biomarkers such as C-reactive protein, fibrinogen or interleukin 6, along with other conventional demographic and physiological measurements, to assess longer term risk of decline in lung function, hospitalisations and mortality. The well-tried model used in cardiovascular disease to assess absolute risk might possibly be adapted for use in COPD, and this should be actively explored.