Ferroelectric domain observation by static piezoelectric deformation has been described by Gruverman et al. If the observed protrusions are caused by piezoelectric deformation induced by depolarization fields of domains, as suggested in the article, serious questions arise. The author believes that the protrusions are not ferroelectric domains. In imaging static deformation, it is difficult to distinguish corrugation due to piezoelectric deformation from those of the other possible causes.