A set of structure utilities has been included for various applications such as: the transformation of unit cells  ([http://www.cryst.ehu.es/cryst/celltran.html CELLTRAN]) or complete structures ([http://www.cryst.ehu.es/cryst/transtru.html TRANSTRU]); strain tensor calculation ([http://www.cryst.ehu.es/cryst/strain.html STRAIN]); assignment of Wyckoff Positions ([http://www.cryst.ehu.es/cryst/wpassign.html WPASSIGN]); equivalent descriptions of a given structure ([http://www.cryst.ehu.es/cryst/equivstru.html EQUIVSTRU]); comparison of different structures with support for the affine normalizers of monoclinic space groups. [http://www.cryst.ehu.es/cryst/rel.html STRUCTURE RELATIONS] calculates the possible transformation matrices for a given pair of group-subgroup related structures.