The aim of this paper is to provide a plausible possibility to analyse bidirectional syncretism patterns of the type Stump (2001) has described for several languages. For many morphological frameworks an analysis of these syncretism patterns poses several problems, because one must stipulate directional rules to ensure the right marker distribution. The mechanism can be seen as a possible extension for many morphological frameworks. The starting point of this mechanism is the assumption that there need not be a radically underspecified elsewhere marker, because one can think of other possibilities to avoid paradigmatic gaps. One of these possibilities is Case Borrowing which allows us to derive many bidirectional syncretism patterns without difficulties.