This paper describes a new approach for generation, representation and selection of assembly sequence alternatives. In the presented methodology, geometric and mobility constraints extracted directly from the CAD model of the assembly are translated into two types of uni-directional matrices, which are called the contact and the translational functions. An algorithmic procedure is used to generate all feasible assembly sequences from these two functions. The sequences are then represented as a table of assembly states and assembly tasks in a hierarchical fashion starting from individual components in unassembled state to finished assembly. This assembly sequence table (AST) is also provided with editing features to apply strategic constraints in order to analyze all feasible sequences and determine the final sequence choice. An example has been provided to demonstrate the proposed approach.