Inflammatory polyarthritides are major causes of invalidity and morbidity. Treatment of rheumatoid arthritis (RA), the most common and most severe of these diseases, is clearly more effective when initiated early using aggressive therapeutic protocols. The recent availability of very effective but extremely costly biologic agents may further improve our treatment strategies. Specific arthritides (e.g., RA) were defined using sets of criteria that are unable to define prognosis and cannot be used to select which patients, early in the course of their disease, should be treated aggressively. A number of putative prognostic markers of severity are available, including anti-Sa and anti-Cyclic Citrullinated peptides (Anti-CCP) antibodies (Abs), whose presence is highly specific to RA. Anti-Cit Abs might characterize one of the severe subsets of RA, both clinically and pathogenically. However, these markers are not yet demonstrated to risk-stratify patients with arthritis of recent onset.