Symbolic analysis traditionally suffers circuit size problems as the number of symbolic terms generated can grow exponentially with the circuit size. This problem has been partially mitigated by a graph-based approach, called Determinant Decision Diagram (DDDs) , where the symbolic terms are implicitly represented in a graph, which has been inspired by the success of Binary Decision Diagram (BDDs)  as an enabling technology for industrial use of symbolic analysis and formal verification in digital logic design. DDD-based symbolic analysis enables the exact symbolic analysis of many analog circuits substantially larger than the previous methods and open new applications for symbolic analysis. DDD-based symbolic analysis still remains the most efficient symbolic analysis technique. This chapter will present basic concept of DDDs, the most efficient DDD construction method based on logic operation, s-expanded DDDs for generating s-expanded polynomials and transfer functions. We will also show how DDDs and s-expanded DDDs can be used for constructing simplified symbolic expressions.