Procedures employed in the development and validation of a new Optimism & Pessimism Scale are described, and information about test-retest reliability is reported. Internal consistency analyses and other data suggest that optimism and pessimism are not polar opposites and bring up questions about the intrerelatedness of the cognitive and affective realms. The magnitude of the correlation between pessimism and measures of anxiety suggests a link between this measure and the Negative Affectivity construct, and the potential relationships among optimism, pessimism, the Pollyanna Principle, and Positive and Negative Affect are discussed. Conceptually, it appears that optimism and pessimism may aid in psychological defense by helping to bind anxiety.