The Next Generation Air Transportation System (NextGen) is an ambitious collaborative effort between government agencies and industry to increase the capabilities of the current air traffic system. Under NextGen, tools are being developed to support air traffic controllers in many aspects of their jobs. However, budgetary constraints, unanticipated technological hurdles and other challenges to implementation make it unlikely that every NextGen tool in development will find its way into future air traffic control facilities. Information is needed to prioritize NextGen tool development to ensure that the tools that will provide the most benefit can be implemented in the appropriate facilities. Toward this end, a web-based survey was conducted of 174 air traffic control tower controllers to identify the perceived usefulness of 10 planned NextGen tower capabilities designed to provide or support: departure metering at the ramp, taxi routing, departure runway assignments, departure flow management, runway scheduling, runway configuration management, integrated arrival/departure scheduling, enhanced surveillance, electronic flight data, and tower data communications. Along with brief descriptions of each of the planned capabilities, surveyed tower controllers were asked to indicate the extent to which each capability would help them in their job and affect capacity, efficiency, flexibility, predictability and safety at their airport. Results indicated that different NextGen capabilities were perceived as useful across different tower facilities. Implications for the prioritization of NextGen tool development are discussed