Mauritania’s economic growth has been largely driven by high commodity prices, leaving the country vulnerable to shocks. From 2009 to 2015, real gross domestic product (GDP) grew by an average of 4.2 percent a year, primarily driven by rising commodity prices. The value of its exports more than doubled between 2009 and 2013. The mining boom and extensive foreign investment in the sector have boosted growth in the construction, utilities, transport, and communications sectors while agriculture and fisheries have fallen behind. Budget execution has improved as actual spending has started to match budgeted amounts more closely in recent years. However, the overall figures disguise much greater discrepancies in individual line items, with significant variance even in relatively straightforward areas such as debt servicing. Public spending on social sectors remains below regional levels, health and social affairs grew, while the share of justice and sector ministries declined. However, a large share of expenditure remains discretionary and unidentified: 30 percent of total expenditures are reported as ‘unspecified expenses’ and are not classified by economic category, which greatly complicates public expenditure monitoring and proper expenditure recording. Mauritania should enhance the transparency and quality of its fiscal data by: (i) auditing the national oil fund, (ii) increase budget credibility and discipline by minimizing ‘unspecified expenses’ and by properly recording all expenditures (iii) reviewing public-sector staffing (iv) keeping its public financial database (BOOST) up to date to reflect its original and revised budgets, and (v) strengthening financial oversight of SOEs through regular performance monitoring and publication of annual financial audits. The government has become dependent on external assistance for investment, creating problems of planning, coordination and insufficient consideration of ongoing maintenance costs. A very small proportion of the investment has benefited rural electrification. Reforms of the sector should concentrate on: (a) urgently reducing SOMELEC technical and commercial losses, (b) reducing reliance on imported fuel oil by investing in alternative energy sources and pushing ahead with the Banda gas to power project, (c) revising SOMELEC’s tariff structure, (d) targeting subsidies to mitigate the impact of revised tariffs on the poor, (v) promoting rural electrification, (e) developing electricity networks particularly in the Senegal River Valley, (f) improving SOMELEC’s governance and management, and (g) encouraging public-private partnerships for investments in new infrastructure.