Siromaskul (2010) defines a Diverging Diamond Interchange as a standard diamond interchange with the key difference being a shift in the crossroad traffic in the interchange. Meaning that traffic on the crossroad crosses paths twice as traffic is shifted to the left side of oncoming traffic allowing left turn movements to occur without impeding oncoming traffic. This paper covers the basics of a diverging diamond interchange design starting at the beginning of the planning process and running through design. The paper covers the optimum site choice, signal timing and phasing, traffic analysis methodology, freeway operations, lane configuration, signalization and weaving/ramp signalization.