Before all the CAT 2007 aspirants give up on me, here is another big chapter on geometry to whet their appetite for CAT quant. CAT 2008 aspirants are also advised to assimilate the following theorems and results into their system as the present chapter covers one of the most important topics in MBA entrance exams- circles. Time and again, I have been told that students either have a knack for geometry or they don’t. During my three years as a quant instructor, I have seen many instructors and students who could not make head or tail of geometry in the beginning, but who worked hard at memorizing and practicing all the theorems and slowly became very good at it, and developed the required visualization powers. One thing is for sure; if you aspire to do an MBA, you are surely not escaping from geometry. And here comes one more heavy geometry dose- circles.