Purpose of review This review will catalog the many recent longitudinal studies that have investigated the relationship between asthma and lung function, or the persistence and trajectories of lung function deficits. Recent findings Recent work has reported on 50-year follow-ups of some prominent population cohorts. A history of asthma confers a 10-30-fold risk of chronic obstructive pulmonary disease. Individuals reaching a reduced maximum growth of forced expiratory volume in 1 s in early adulthood are at risk for early or more severe chronic obstructive pulmonary disease (COPD). Summary Taken together, there is a wealth of overlapping cohort studies of lung function, asthma and COPD. These show that asthma is associated with reduced lung function, which may start in infancy or prenatally, persists through childhood and adulthood and predisposes for early or more severe COPD.