As already noted, ICD-10 will be mandated for use by 2013. The categories for chronic lower respiratory diseases have already been finalized and are similar to those in ICD-9. However, the number system is completely different and falls under codes J40-J47. The terminology of chronic bronchitis (J41 and J42) and emphysema (J43) persist as in ICD-9, but with slightly different subclasses. There is now an additional category of “Other chronic obstructive pulmonary disease,” J44, which excludes emphysema and chronic bronchitis, but does make an attempt to differentiate exacerbations (J44.1) from what we presume is stable disease. This is analogous to the category of 496, “Chronic airway obstruction, not elsewhere classified,” and is often used as an easy way out, adding nothing to the value of such coding. However, the inclusion of detailed forms of emphysema (viz, panlobular, centrilobular, interstitial, and compensatory) is not likely applicable to clinical practice. Asthma has its own category (J45), but is still subdivided into J45.0 (predominantly allergic), J45.1 (nonallergic), J45.8 (mixed), and J45.9 (unspecified, including late-onset). In addition, there is now a separate code for status asthmaticus, defined as acute severe asthma, J46.