In this thesis, we consider the assembly/disassembly line balancing (ADLB) problem. The studies in the literature consider assembly and disassembly problems separately and use task precedence diagram (TPD) and AND/OR Graph (AOG) in assembly and disassembly line balancing problems, respectively. In contrast to these studies, we use AOG for both assembly and disassembly line balancing problems, considering these two problems as complementary of each other. Hence, we call the complementary problem as ADLB-AOG. We show theoretically that AOG is a more general version of the TPD. We also develop integer programming (IP) and dynamic programming (DP) formulations to solve the ADLB-AOG problem. Our analysis indicates that the DP formulation performs much better than the IP formulation in terms of the problem sizes that can be optimally solved. We also develop a DP-based heuristic to solve large-size instances of the ADLB-AOG problem. An experimentation of the procedures on some sample problems and the implementation of the heuristic on a sample problem are also given.