Market access and welfare: Is there a conflict?

•A local optimal tariff reform can increase both welfare and market access.•A welfare-based and a market-access-based optimal reforms are dual to each other.•Optimal reforms increase both objectives if initial ad valorem tariffs are uniform.

Well known tariff reform rules that are guaranteed to increase welfare will not necessarily increase market access, while rules that are guaranteed to increase market access will not necessarily increase welfare. The present paper proposes a new set of tariff reforms that can achieve both objectives at the same time.