The commercial systems using intelligent textiles that start to appear on the market perform physiological measurements such as body temperature, electrocardiogram, respiration rate, etc. and target sport and healthcare applications. Biochemical measurements of body fluids combined with available health monitoring technology will extend these systems by addressing important health and safety issues. BIOTEX, standing for Bio-sensing Textile for Health Management, is a European project, which aims at developing dedicated biochemical sensing techniques that can be integrated into textiles. Such a system would be a major breakthrough for personalized healthcare and would allow for the first time the monitoring of body fluids with sensors distributed in a textile substrate. The potential applications include isolated people, convalescents and patients with chronic diseases, sports performance assessment and training. The project is addressing several challenges, among which: sweat collection and delivery to the sensors, high sensitivity with a wearable system, wearability issues, sensor calibration and lack of research in sweat analysis.