In his challenge paper, Kym Anderson makes a strong case for maximum liberalization of trade, not only as a good in itself, but also as a way to contribute to the other high-priority challenges. Both opponents agree that free trade has economic benefits, but have concerns about how these might best be generated and shared.

Arvind Panagariya whole heartedly supports Anderson's case for trade liberalization to be the highest priority among the challenges and, indeed, considers it essential if all the others are to be met. Nevertheless, he has some critical points to make. In particular, he thinks that the case would be stronger if more details were given of the nature and size of some of the barriers. Also, benefits are not uniformly distributed: The impact on some developing countries would actually be negative.

Anderson makes the case for liberalization on the basis of broad generalizations, where cause (liberalization) inevitably leads to the desired effect (increased growth). In Panagariya's view, this relationship cannot be guaranteed, and he sees openness instead as being necessary, but not sufficient, for sustained rapid growth.

Looking at the first of Anderson's identified opportunities – unilateral liberalization – Panagariya sees ample evidence for the benefits of this, citing in particular the dramatic improvements in growth resulting from India and China following such a path.