  The boundary conditions, customarily used in the Landau-type approach to
ferroelectric thin films and nanostructures, have to be modified to take into
account that a surface of a ferroelectric (FE) is a defect of a ``field'' type.
The surface (interface) field is coupled to a normal component of polarization
and, as a result, the second order phase transitions are generally suppressed
and anomalies in response are washed out, as observed experimentally.
