A general fusion method to find solutions to the reflection equation i
n higher spin representations starting from the fundamental one is sho
wn. The method is illustrated by applying it to obtaining the K diagon
al boundary matrices in an alternating spin 1/2 and spin 1 chain. The
Hamiltonian is also given. The applicability of the method to higher r
ank algebras is shown by obtaining the K diagonal matrices for a spin
chain in the {3} representation of su(3) from the {3} representation.