This paper sketches the vision and first results of a 'Personal Health Assistant' PHA, opening up new vistas in patient centred healthcare. The PHA is comprised of a wearable sensing and communicating system, seamlessly embedded in daily clothing. Several on-body sensors monitor the biometric and contextual status of the wearer continuously. The embedded computer fuses the vital and physiological data with activity patterns of the wearer and with the social environ-ment; based on these data the on-body computer generates the 'Life Balance Factor' LBF as an individual feedback to the user and to the surroundings afford-ing effective disease prevention, management and rehabilitation, the last also involving telemedicine. The state-of-the-art enabling technologies: smart textile technology and miniaturization of electronics combined with wireless communication, along with recent developments in wearable computing are presented and assessed in the context of multiparameter health monitoring.