This paper compares ad valorem and specific taxes in asymmetric homogenous
Cournot oligopolies with constant marginal costs. We show that for any give
n level of industry output, ad valorem taxes are superior to specific taxes
in terms of revenue raised. If the tax rates are sufficiently high, for an
y given specific tax one can find an ad valorem tax that leads to greater t
ax revenue, consumer surplus, and industry profits.