The aim of this paper is to draw chemists' attention to the chirality of sq
uare planar complexes and to ensure that authors of publications take this
chemical aspect into consideration. Some simple prochiral or chiral complex
es of Pd(II) or Pt(II) with 2-methyl or 2-ethylpyridine were prepared and s
tructurally characterized by X-ray diffraction methods in order to prove th
at the chirality in square planar complexes is a rather common event. The s
ituation regarding the stereodescriptors for axial chirality, planar chiral
ity and helicity is both confused and confusing and in our opinion it would
be better to adopt only the P and M terms that are related to the sign of
the appropriate torsion angles.