To enable future robotic exploration systems to have greater mobility, sensing, sampling, and communication capabilities on difficult terrain such as craters, cliffs, gullies, and skylights, Tethers Unlimited proposes to develop a "Sensing and Positioning on Inclines and Deep Environments with Retrieval" (SPIDER) system. This system employs an innovative lightweight 'orbital winch' with the capacity for rapid tether deployment and high load retrieval or towing. The unique design of the orbital winch accomplishes cable winding and deployment without rotating the spool, minimizing mass and power consumption, while eliminating the need for electrical and optical slip-ring. The SPIDER system also integrates a launcher that can be used to deploy a wide variety of tethered end-effectors to provide new capabilities for sample retrieval and sensing. A carousel of these stowed end-effectors will allow selection of appropriate implements for a desired task. For example, tethered anchor end-effectors could give planetary rovers the ability to rappel down ravines, tow themselves up steep slopes, or free themselves from a stuck position. Sensing and sampling end-effectors with data- and power- transmitting tethers can be deployed and retrieved from otherwise inaccessible areas, giving in-situ feedback via optical fibers. The SPIDER system can also be a launch platform for subsurface boring or ice-penetrating probes such as the Cryobot. Moreover, by launching an RF transmitter/receiver, the system could improve communications for a planetary rover entering a geologic feature that would impede radio contact, such as a lava tube. The Phase I effort will mature the SPIDER to TRL 4 by testing prototypes of key components, and the Phase II will mature an integrated system to TRL 6 by testing and qualifying a prototype in a relevant terrestrial environment.