International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Wireless interfaces are becoming ubiquitous in terrestrial applications ranging from local area networking in business and commercial environments to large scale factory automation and process control. The pressure to develop these wireless interfacing techniques has come from the need to reduce cabling, reduce installation costs, and make it easier to extend network infrastructures. Concerns about electromagnetic compatibility, safety, reliability, and security have lead to the development of techniques and protocols that enable such wireless interfaces to be operated in electromagnetically harsh environments, without generating unacceptable interference, and providing reliable, dependable and secure data communications. On the face of it, the use of wireless interfaces onboard spacecraft looks like a good way of reducing the spacecraft harness mass and bulk. However, recent work by the European Space Agency has shown that, while harness reduction will undoubtedly be one benefit of using wireless interfaces, they offer many other benefits that will be more significant in the near future. Amongst these are significant advantages during integration and testing, the ability to retrofit and upgrade facilities, and cable replacement in moving structures such as robotic arms. In this paper we briefly survey the benefits of wireless interface technologies for spacecraft onboard use, and identify the challenges involved in adapting them for flight use. We then look at the considerations that should be taken into account in establishing the financial case for developing wireless interface technologies for flight applications.