There is provided a method for estimating the volume of fluid in part of the body of a subject, the method comprising obtaining a measurement of the circumference, c, of the part of the body of the subject obtaining a measurement of the impedance of the part of the body of the subject using electrodes attached across the part of the body of the subject and estimating the volume of fluid in the part of the body of the subject from the measurement of impedance and the measurement of the circumference c. An apparatus comprising a control unit configured to perform the method is also provided.
