  We consider the memory effect in even dimensional spacetimes of dimension $d
\ge 4$ arising from a burst of gravitational radiation. When $d=4$, the natural
frames in the stationary eras before and after the burst differ by the
composition of a boost and supertranslation, and this supertranslation
characterizes the "memory effect," i.e., the permanent displacement of test
particles near infinity produced by the radiation burst. However, we show that
when $d > 4$, this supertranslation and the corresponding memory effect vanish.
Consequently, when $d >4$, it is natural to impose stronger asymptotic
conditions at null infinity that reduce the asymptotic symmetry group to the
Poincare group. Conversely, when $d=4$, the asymptotic symmetry group at null
infinity must be taken to be the BMS group.
