We study site displacement caused by changes in the rate of rotation of the Earth and in the orientation of the Earth's pole. We include small effects which have been previously neglected, most notably those caused by polar motion induced ocean loading. Using very long baseline interferometry (VLBI) data we estimate the real and imaginary Love numbers associated with vertical and horizontal deformations caused by polar motion. The estimates of the real part of the Love numbers are consistent with theoretical predictions, although the imaginary parts are too large. Including the loading effect improves the agreement of the real part. ¿ 1998 American Geophysical Union