  We examine the reducibility of induced from discrete series representations
of $SU_n$ over a $p$--adic field of characteristic zero. Some results are given
for groups sharing derived group. We give a relationship between the $R$-groups
for $U)n$ and $SU_n.$ Nonabelian $R$-groups are discussed. Elliptic
representations are examined and in the generic case we give an explicit
description f those $L$--packets containing non-discrete elliptic tempered
representations. We exhibit $L$--packets containing both elliptic and
non-elliptic components.
