A critical assessment of the so-called “peak temperature methods” (originally proposed by Kissinger) is presented. The two ingredients of peak temperature methods, namely, Kissinger's assumption and transformation equations, are considered. First it is argued that Kissinger's assumption although not being valid for DTA holds for DSC. Then it is shown that the only way to use kinetic parameters obtained from non-isothermal experimental data to describe both iso- and anisothermal kinetics is to take the same reaction rate equation for the two kinetics, as previously done by Henderson.