  Based on numerical simulations, a study of the high temperature, finite
frequency, thermal conductivity $\kappa(\omega)$ of spin-1/2 ladders is
presented. The exact diagonalization and a novel Lanczos technique are
employed.The conductivity spectra, analyzed as a function of rung coupling,
point to a non-diverging $dc-$limit but to an unconventional low frequency
behavior. The results are discussed with perspective recent experiments
indicating a significant magnetic contribution to the energy transport in
quasi-one dimensional compounds.

Strongly Correlated Electrons;Statistical Mechanics