Favorable alignment of regio-irregular poly(3-alkylthiophene)s in a film can be attained, despite the fact that these polymers lack an intrinsic tendency to form well-ordered supramolecular aggregates. As reported here, alignment can be achieved simply by oxidizing the polymer in solution prior to film formation. A delicate balance between the degree of order and the level of oxidation in solution is observed. These results point to a way to improve charge transport efficiency, which is influenced by intra- and interchain order in the polymer.