Innovation in textiles and clothing has embodied various combinations of new and existing materials to meet conventional needs of comfort and fashion. Interactive and intelligent textiles are emerging as many new textile materials are being used to form sensors in garments to intimately interact with the human form. Interactive textiles typically contain sensors located within a garment to detect physiological functions that are wirelessly connected to digital infrastructure and application specific software. These devices can be realised in conventional garments and have scope for application in diverse fields including entertainment, education, sport, military and medicine. Position and Motion Sensing devices will be discussed for each application, in terms of the value proposition, performance requirements, regulations, and existing technology. A case study of an entertainment device that uses limb motion to achieve an imaginary instrument, the Wearable Instrument Shirt (WIS) will be discussed in this context. The WIS combines a wearable sensor interface with software to map gestures and audio data files to form an easy-to-use gesture driven instrument that allows real-time interactive musical performances without any need for significant instrument or computer skills.