The rapid development of the Isokinetic Relationship IKR, especially c
oncerning its applications to actual chemical reaction series, is revi
ewed. It is proved on the basis of several examples that the IKR is ex
tremely sensitive to changes in reaction pathways, and that this can b
e used as a powerful tool in distinguishing changes within a given ser
ies of reactions, provided temperature-dependent data are available. I
t is hoped that the examples presented in this Review will encourage o
thers to use the effect for detailed investigation of their own reacti
on series, especially as a simplified, reliable statistical analysis i
s now available.