Special and Differential Treatment (SDT) was introduced into the GATT/WTO architecture to help developing and least-developed
countries (LDCs) surmount structural disadvantages and share in the gains from trade liberalisation. Six decades after its inception,
this paper asks whether SDT has in fact met its stated objectives: (i) increasing equity in the multilateral trading system, (ii)
expanding market access for developing-country exports, and (iii) accelerating income growth and poverty reduction in beneficiary
countries.
Combining a comprehensive review of negotiated tariff outcomes (1967-2023) with an econometric assessment of trade performance
and poverty trajectories, we find that SDT has fallen short on all three counts. Average tariff reductions on products of export interest
to developing countries have consistently lagged those granted to developed-country goods. Aggregate export shares of the poorest
economies have stagnated or declined, while intra-South competition has intensified because large, advanced developing economies
self-select into the same flexibilities that were intended for structurally weak economies. Moreover, the absence of objective

graduation criteria has allowed “free-riding” by high-income members that continue to claim SDT, diluting the benefits available to
LDCs. Quantitative tests reveal no statistically significant relationship between the depth of SDT flexibilities received and either
export diversification or poverty reduction in beneficiary countries. These findings suggest that SDT’s original conceptual
design—non-reciprocal preferences and extended implementation periods—has been undermined by an institutional failure to link
eligibility to actual development needs. We therefore conclude that SDT, as currently applied, has not achieved its objective. To
restore credibility, we propose a rules-based “differentiated differentiation” framework that ties each SDT provision to transparent,
indicator-driven thresholds and automatic graduation triggers, ensuring that only countries that genuinely need assistance receive it
and only for as long as the need persists