Modular structural system

A modular structural system for building structural models or for constructing actual structures. The system includes at least one connector hub member comprising a plurality of projections arranged in a plurality of planes each for engaging an end of a strut member, with all projections having cross sectional geometries identical with cross sectional geometries of attached strut members at sites of respective attachment. Second, the system includes at least one strut member having a first end and a second end, with each end having an engageable portion for engagement with a projection of the connector hub member. The strut member has a strut cross-sectional geometry identical to and in alignment with the cross-sectional geometry of a projection and adjacent protuberances of the hub member when the strut member is engaged with the projection. Such cross-sectional geometry can be chosen as desired or required for any particular application, with the singular requirement being that cross-sectional strut geometry and cross sectional hub geometry are the same at the site interface. Retention members are included for securing the respective ends of the strut members with the projections of the connector hub members. The strut members can have along their respective exposed surfaces flanges or the like capable of accepting and retaining panels or other finishing construction material.