THE MK-III SPACE SUIT TECHNOLOGY DEMONSTRATOR WAS DEVELOPED IN THE 1980S AS A PROTOTYPE TO SERVE AS A TEST BED TO INVESTIGATE DIFFERENT TYPES OF SUIT JOINT MOBILITY SYSTEMS THAT CAN BE USED IN THE DESIGN OF FUTURE PLANETARY EXPLORATION SPACE SUITS. THE HARDWARE ON THE SPACE SUIT WAS- AND STILL IS- FABRICATED AND DESIGNED BY AIR-LOCK, INC.; THE SOFT GOODS WERE A PRODUCT OF ILC DOVER. OVER THE PAST 20 YEARS, THE USES FOR THE MK-III SPACE SUIT TECHNOLOGY DEMONSTRATOR HAVE BEEN QUITE VARIED. MOST RECENTLY THE SUIT HAS BEEN SERVING IN COMPARATIVE SPACE SUIT TESTING WITH OTHER STYLES OF PROTOTYPE SPACE SUITS AND CURRENT FLIGHT PROGRAM SPACE SUIT CONFIGURATIONS. THE COMPARATIVE ANALYSIS ALLOWS ENGINEERS TO PUT QUANTITATIVE VALUES TO THE SUBJECTIVE DATA THAT HAS BEEN COLLECTED WITH RESPECT TO SUIT MOBILITY. TEST DATA IS BEING USED BY THE EXPLORATION PROGRAM TO DEVELOP REQUIREMENTS FOR LUNAR SURFACE EXTRA VEHICULAR ACTIVITY TASKS. FUNCTIONAL MOBILITY RANGE OF MOTION TESTING HAS INCLUDED THE FOLLOWING ACTIVITIES: WALKING, CRAWLING, KNEELING, ASCENDING AND DESCENDING A LADDER, TRANSLATING UP AND DOWN AN INCLINED SURFACE, SHOVELING, HAMMERING, INGRESSING AND EGRESSING SEATS, AND THE OPERATION OF MULTIPLE HATCH ACTUATION CONCEPTS. FURTHER THE MK-III, HAS BEEN UTILIZED ON THE REDUCED GRAVITY AIRCRAFT FOR INTERFACE FEASIBILITY TESTING WITH THE CONSTELLATION PROGRAM ORION VEHICLE SIDE HATCH, THE LOW IMPACT DOCKING SYSTEM TUNNEL, AND MICRO-GRAVITY SPACE SUIT DON AND DOFF TESTING. THE MK-III SPACE SUIT TECHNOLOGY DEMONSTRATOR ALSO SERVES AS THE PRIMARY SUIT FOR THE DESERT RESEARCH AND TECHNOLOGY STUDIES CONDUCTED EACH YEAR IN ARIZONA. THE DESERT RESEARCH AND TECHNOLOGY STUDIES ACTIVITIES CENTER AROUND THE DEVELOPMENT AND TESTING OF HARDWARE AND MISSION OPERATIONS ANTICIPATED FOR FUTURE PLANETARY EXPLORATION PROGRAMS. MOST NOTABLY, THE MK-III SPACE SUIT TECHNOLOGY DEMONSTRATOR HAS BE USED TO STUDY THE INTERFACES BETWEEN A SUITED SUBJECT AND THE SCIENCE, CREW, OPERATIONS AND UTILITY TEST BED (SCOUT), WHICH IS A COMBINATION PLANETARY ROVING VEHICLE AND ROBOTIC ASSISTANT. THE INTERFACES STUDIED INCLUDE THE SUIT TO SEAT INTERFACE, THE SUIT TO DISPLAYS INTERFACE, AND THE SUIT TO CONTROLS INTERFACE.