  We compare theoretical expectations for the Casimir force with the results of
precise measurements. The force is calculated at finite temperature for
multilayered covering of the bodies using the Lifshitz theory. We argue that
the dielectric function of the metallization has to be directly measured to
reach the necessary precision in the force calculation. Without knowledge of
this function one can establish a well defined upper limit on the force using
parameters of perfect single-crystal materials. The force measured in the
torsion pendulum experiment does not contradict to the upper limit. Importance
of a thin Au/Pd layer in the atomic force microscope experiments is stressed.
The force measured with the microscope is larger than the upper limit at small
separations between bodies. The discrepancy is significant and reproduced for
both performed measurements. The origin of the discrepancy is discussed. The
simplest modification of the experiment is proposed allowing to make its
results more reliable and answer the question if the discrepancy has any
relation with the existence of a new force.
