A four-factor model of spiritual intelligence is first proposed. Supportive evidence is reviewed for the capacities of critical existential thinking, personal meaning production, transcendental awareness, and conscious state expansion. Based on this model, a 24-item self-report measure was developed and modified across two consecutive studies . The final version of the scale, the Spiritual Intelligence Self-Report Inventory , displayed excellent internal reliability and good fit to the proposed model. Correlational analyses with additional measures of meaning, metapersonal self-construal, mysticism, religiosity, and (...) social desirability offer support for construct and criterion-related validity. According to both intelligence criteria and current psychometric standards, findings validate the proposed model and measure of spiritual intelligence. Future directions are discussed. (shrink)