The productivity of present day industrial robots may be hampered by phenomena such as vibrations and deformations which appear whenever they are made to move at high speeds or to carry heavy payloads. To address this problem, many researchers have studied the flexibility of robot arms. Most works, however, rely on simple one or two-link flexible arms made with extremely flexible beams which operate at very slow speeds. Thus their results may prove difficult to apply to more realistic situations. The CEIT flexible robot is a lightweight three degree of freedom flexible arm which has been built to bridge this gap between flexible and industrial robots. The structural behavior of this robot is investigated through experimental modal analysis. The procedure and results of the analysis are described in this paper.< >