  We investigate the impact on low energy flavour mixing phenomena of the
renormalisation group running of parameters in supersymmetric theories. We have
explicitly chosen flavour dependent supergravity couplings. The renormalisation
group equations are displayed in general matrix form. We work in a scale
dependent basis such that the hierarchy in the quark masses can be more easily
utilised. Simple analytic solutions are provided in matrix form (for general
boundary conditions) when only the third generation Yukawa couplings are
retained in the renormalisation group equations. We solve the evolution
equations of the KM matrix and the supersymmetry breaking soft terms in the
squark sector. We suggest a general parametrisation of the soft analytic terms,
more suitable for non-universal supergravity couplings. We point out that for
flavour dependent soft terms, there are new contributions to the neutron
electric dipole moment. Finally, we consider a model with maximal flavour
mixing in order to estimate the effects due to the renormalisation scale
dependence.
