Anticholinergics are agents of first choice for the symptomatic treatment of patients with COPD. Tiotropium (Ba 679 BR, Spiriva) is a long-acting inhaled anticholinergic designed for once-daily bronchodilator treatment of COPD. Tiotropium is a selective antagonist of pulmonary M1 and M3 muscarinic receptor subtypes, that produces a long-lasting (24 hours), dose-dependent bronchodilation and bronchoprotection against constrictive stimuli, e. g. methacholine, following inhalation of single doses. Clinical trials with tiotropium in COPD patients over a maximum treatment duration of one year have confirmed a persisting bronchodilator effect of tiotropium compared with placebo and ipratropium, as well as meaningful clinical improvements in lung function, hyperinflation, exercise tolerance, symptom control and quality of life. Moreover, recent trials indicate that treatment with tiotropium also reduces the frequency of COPD exacerbations and hospitalizations. Comparative trials further suggest that the bronchodilator potency of tiotropium may be superior to those of available COPD treatments. Besides a higher incidence of dry mouth, the side effect profile was comparable to ipratropium bromide. In conclusion, present clinical data suggest that tiotropium has the potential of a first-line treatment for patients with COPD.