  We compute several coefficients needed for O(a) improvement of currents in
perturbation theory, using the Brodsky-Lepage-Mackenzie prescription for
choosing an optimal scale q*. We then compare the results to non-perturbative
calculations. Normalization factors of the vector and axial vector currents
show good agreement, especially when allowing for small two-loop effects. On
the other hand, there are large discrepancies in the coefficients of O(a)
improvement terms. We suspect that they arise primarily from power corrections
inherent in the non-perturbative methods.
