The National Economic Advisors undertook an assessment of Regional Cooperation for Development and Stability for the Horn of Africa (HoA) countries of Djibouti, Eritrea, Ethiopia and Somalia at the behest of the Somali authorities. The principal objectives of the study are to document the current state of economic and social performance of the sub-region, and the rationale for intensifying cooperation in trade and investment, and economic infrastructure fields. In particular, the study assesses the benefits and challenges facing the implementation of enhanced regional cooperation for the Development and Stability Partnership (DSP). There has been strong momentum in the Horn of Africa sub-region to promote cooperation across a range of issues; primarily in resolving long-standing conflicts, entering into political dialogue, and initiating joint initiatives to explore closer economic engagements. However, the economic cooperation attempts, thus far, have been general and less rooted in specific commitments and measures to move the process forward. Given the enormous challenges facing the sub-region, the authorities ought to utilize evidence-based reforms and specific measures to realize transformative changes.