The classification of defenses into affect and content focused is examined in the light of modern theorizing about defensive processes. The results of two studies into the factor structure of the Defense Style Questionnaire (DSQ) are reported. The results indicate that the classification into levels by Vaillant is both empirically robust and theoretically meaningful. The two studies are presented as complimentary due to the predominance of female gender in study 1 and male gender in study 2. Implications for future research and clinical practice are explored, particularly in relation to personality and anxiety disorders.