This chapter presentsthe conceptual and analytical basics of feedback in a carefully integrated way. The analytical details presented herecan alsobe found many other places:root locus, Black's formula,the fundamental oscillation condition, and the like are treated in many places. What is often missing in texts for the advanced student are the conceptual insights.Why, for instance, is the phase response of the loop transmission so important?What does it mean for a complex pole pair to "dominate" a system response, and why is such dominanceso common? Why is open-loop control better for speed than closed-loop control? As always, conceptual understanding and analytical mastery are mutually reinforcing.