THE RAPID RISE OF ADDITIVE MANUFACTURING (AM) IS USHERING IN EXCITING NEW POSSIBILITIES FOR DIRECT FABRICATION OF NOVEL AEROSPACE COMPONENTS. NO LONGER CONFINED TO CONVENTIONAL FABRICATION PROCESSES MANUFACTURING OF SPACECRAFT STRUCTURES WILL INCREASINGLY AND ROUTINELY EXPLOIT NEW MATERIALS AND PROCESSES THAT EITHER PROVIDE OR INHERENTLY RELY ON THE CAPABILITY FOR ARCHITECTING THE INTERNAL STRUCTURE AND OVERALL SHAPE OF BOTH MATERIALS AND COMPONENTS. THE TRANSITION TOWARDS THIS NEW MANUFACTURING PARADIGM IS DRIVEN BY THE EMERGING CAPABILITY TO ENGINEER ON-DEMAND LIGHTWEIGHT (MULTI)FUNCTIONALITY AND SUPERIOR MATERIAL PROPERTIES AT LEVELS THAT ARE BEYOND THE SCOPE OF TRADITIONAL MANUFACTURING METHODS USED FOR BUILDING SPACECRAFT SYSTEMS TODAY. THE USE OF AM IS ITSELF REVOLUTIONARY BUT FURTHER TRANSFORMATIVE ADVANCES ARISE WHEN AM IS COMBINED WITH TOPOLOGY OPTIMIZATION (TO) A SYSTEMATIC OPTIMIZATION-DRIVEN DESIGN METHOD. THE RESEARCH PROPOSED HEREIN SEEKS TO EXPLOIT THIS POTENTIAL BY RIGOROUSLY INTEGRATING TOPOLOGY OPTIMIZATION THE MANUFACTURING CAPABILITIES AND RESULTANT MATERIAL PROPERTIES OF ADDITIVE MANUFACTURING AND THE MULTI-FUNCTIONAL PERFORMANCE REQUIREMENTS OF SECONDARY STRUCTURES FOR SPACE APPLICATIONS. THIS INTEGRATION WILL REQUIRE THE DEVELOPMENT OF NEW MATHEMATICALLY RIGOROUS TOPOLOGY OPTIMIZATION ALGORITHMS THAT PROPERLY ACCOUNT FOR AM GEOMETRIC CONSTRAINTS AND ANISOTROPIC AND VARIABLE MATERIAL PROPERTIES ALL OF WHICH ARE PROCESS- AND BUILD-DIRECTION DEPENDENT. CHARACTERIZATION ACTIVITIES ARE NEEDED TO INFORM THE TO DESIGN ENGINE OF REPRESENTATIVE MATERIAL BEHAVIOR AS WELL AS VALIDATE THE TO MODELS AND FABRICATION INNOVATIONS ARE NEEDED TO ELIMINATE UNPREDICTABLE FAILURE MECHANISMS PARTICULARLY RELATED TO SURFACE ROUGHNESS-INDUCED FRACTURE. THE RESULTING INTEGRATED FRAMEWORK WOULD ENABLE THE ULTIMATE GOAL OF REALIZING ULTRA-EFFICIENT STRUCTURES WHOSE EXTERNAL SHAPE AND INTERNAL MATERIAL ARCHITECTURE ARE FULLY OPTIMIZED TO MEET MULTIPLE APPLICATION-RELEVANT DEMANDS. ALTHOUGH WE SEEK A GENERAL FRAMEWORK THIS RESEARCH PROGRAM IN PARTICULAR WILL FOCUS ON 3D SECONDARY SUPPORT STRUCTURES FOR EQUIPMENT MOUNTING AND SECONDARY STRUCTURAL SUPPORTS FABRICATED FROM ALUMINUM AND TITANIUM ALLOYS WHICH WHEN OPTIMIZED WILL LEAD TO LIGHTWEIGHT POROUS SYSTEMS OFFERING SPECIFIC STIFFNESS OF E0.5/>3000 KPA0.5CM3/G (E0.5/>2000 KPA0.5CM3/G) FRACTURE TOUGHNESS OF KIC>5 MPA-M0.5 ENHANCED ENERGY DISSIPATION CAPABILITIES AND TAILORABLE THERMAL CONDUCTION. IF SUCCESSFUL THIS FLEXIBLE DESIGN-MANUFACTURE APPROACH HAS THE CAPABILITY TO DESIGN AND REALIZE ULTRA-LIGHTWEIGHT LATTICE SYSTEMS TREMENDOUSLY ENHANCING FUTURE SPACE FLIGHT AFFORDABILITY AND CAPABILITIES.