With the emerging space activities, use of deployable structures for aerospace applications increased in recent years. Deployable masts are special types of these structures where longitudinal deployment is required and deployable truss mast is one of the deployable mast types. In this thesis, a new design methodology for deployable truss masts is introduced resulting in superior packing ratio. It is a type of a Wren platform which has a single degree of freedom, and it is called HiDAM: Highly Deployable Articulated Mast. The mathematical model for HiDAM is constructed and the packing ratio is maximized by optimizing part lengths. Considering the set design requirements, the constructional design is carried out, first in two dimensions where mathematical model is developed, then in three dimensions. Along with the constructional design, the prototype of HiDAM is manufactured and assembled for a single deployable unit with which overall mechanism movement can be seen. It is presented that with the proposed deployable truss mast HiDAM, the packing ratio can be increased by about 12% compared to the most recent deployable truss mast examples in the literature.