Allergic rhinitis is a global health problem. Over 600 million patients suffer from this disease worldwide. ARIA (Allergic Rhinitis and its Impact on Asthma), an evidence-based document, was produced and published in 2001 using an extensive review of the available literature. The ARIA 2008 update was recently published and covers tertiary prevention of allergy, pharmacologic treatments, and immunotherapy. Nonallergic rhinitis is still a controversial area and may pose some treatment problems. Another important aspect of the ARIA update is the comorbidity of allergic rhinitis, in particular, asthma. The recommendations of the 2008 ARIA Update, as in 2001, are that patients with allergic rhinitis, particularly if persistent, should be evaluated for asthma, patients with asthma should be evaluated for rhinitis, and an effective and safe combination strategy should be used to treat diseases of the upper and lower airways. Over the last few years, severa studies performed in Spain report new data on the prevalence of allergic rhinitis sensitivity to common aeroallergens, comorbidity of allergic rhinitis and asthma, and impact on quality of life. The studies reviewed in this manuscript confirm--as do those from other developed countries--the enormous impact of the disease on society and health care in Spain.