  We develop a general theory of Fermi liquids to discuss the Kadowaki-Woods
relation $A\propto \gamma^2$. We derive a formula for the ratio $A/\gamma^2$
which is expressed as a product of two dimensionless parameters $\alpha$ and
$F$, where $\alpha$ represents a coupling constant for quasiparticle scattering
and $F$ is a geometric factor determined by the shape of the Fermi surface.
Then we argue that the universal ratio observed in heavy fermion compounds is
reproduced under the conditions $\alpha\sim 1$ and $F\sim 20$. The former is
regarded as a universality of Fermi liquids in a strong coupling regime, and
the latter is corroborated by evaluating $F$ definitely in simple cases. It is
noted that the proportional relation is just an example of the universal
phenomena to be expected for the whole class of strong coupling Fermi liquids.

Condensed Matter