This application describes a new, non-invasive, non-cuff technique for measuring arterial or venous blood pressure. Currently, blood pressure is measured using invasive catheter-based direct methods, or non-invasive indirect Riva-Rocci/Kirotkoff (cuff-based) variants which only measure arterial blood pressure. The proposed technique can sample pressure many time a second and simultaneously monitor pulse rate and arterial blood pressure. This approach has the potential to be substantially more accurate and less obtrusive than cuff-based methods and safer than direct methods. It also provides that only non-invasive method for measuring venous blood pressure. In Phase I, a prototype instrument will be built to test the feasibility of this approach. In Phase II, the instrument will be refined and fully tested. PROPOSED COMMERCIAL APPLICATION: With its increased accuracy and capabilities, the proposed device could be prepared over standard cuff- based techniques for non-invasively monitoring arterial blood pressure. It would also provide a currently missing capability for non-invasively measuring venous blood pressure. It could become standard equipment at hospitals and doctors' offices.