Allergic rhinitis (AR) is a global health problem affecting at least 10 to 25% of the population, and is a chronic respiratory illness that affects quality of life, productivity, and other co-morbid conditions such as asthma and sinusitis. Classification of AR has been changed to intermittent/persistent (duration) and mild/moderate-severe (severity) based on the "Allergic Rhinitis and Its Impact on Asthma" (ARIA) workshop report published in 2001. A patient's history and skin prick test results are of utmost importance for its diagnosis regardless of classification system. Treatment should be based on the patient's age, severity, and duration of symptoms. The treatment algorithm has recently been revised by 2008 ARIA guidelines. Treatment options for AR consist of allergen avoidance, pharmacotherapy, immunotherapy, and surgery. Patients should be advised to avoid known allergens and educate themselves about their condition. Although allergen avoidance and immunotherapy are theoretically ideal, intranasal corticosteroids are the most effective treatment in persistent and moderate-severe AR. Sublingual immunotherapy has been introduced and has shown good results in its efficacy and safety. Physicians are advised to be alert to the state-of-the-art knowledge on AR and be willing to take advantage of recent progress on AR.