This summarizes a document discussing Reddin's 3-D model of leadership styles. It begins by introducing Reddin's model which categorizes leadership styles based on combinations of task orientation, relationship orientation, and effectiveness. It then reviews prior research that Reddin's model integrates, such as the Ohio State studies, Blake and Mouton's managerial grid, and various other leadership typologies. The document also discusses how Reddin identified 20 situational elements and derived the eight specific leadership styles from combinations of high and low orientations across the three dimensions.