This doctoral thesis focuses on the evaluation of the World Bank (WB) performance in delivering development aid to the Least Developed Countries (LDCs). For this purpose, an extensive research was performed to analyze a set of 790 Implementation Completion and Results reports for key economic and financial indicators. Results of this research provide various insights for the appraisal and the results stage of project delivery of the LDCs in different continents. In the final part of the economic and financial analysis the minimum Social Return on Investment (SROI) of the LDCs including all project costs was calculated. This SROI ratio outcome of 1 and 1.06 in the weighted and 1.3 and 1.72 in the unweighted case indicate that projects delivered by the WB have a positive effect on the poor countries. In the second part of this research project the data set of the ICR reports was qualitatively researched for negative ratings according to 3 core assessment categories for the overall project performance: Sustainability, bank performance and borrower performance. As a result the most critical categories respectively risks were outlined. In conclusion, the research analyses and findings support the general demand to provide even more development assistance to poor countries.:Table of Tables and Figures List of Equations List of Abbreviations 1 Introduction 1.1 Introduction to the Topic 1.2 Assessing Poverty Problems and Achieving Economic Growth 1.3 Millennium Development Goals 1.4 Development Aid 2 Research Approach 2.1 Objective 2.2 Structure 2.3 Least Developed Countries 2.4 World Bank 2.5 Data Access and Relevance 2.5.1 Data Basis 2.5.2 Implementation Completion and Results Reports 2.5.3 Project Types 2.6 Term “Performance” 2.7 Study and Research Questions 2.8 Challenges of this Doctoral Thesis 2.9 Contribution of this Thesis 3 Economic and Financial Analysis 3.1 SROI Concept 3.1.1 SROI Definition 3.1.2 SROI Process and Impact Map 3.1.3 Cost-Benefit-Analysis 3.1.4 SROI Calculation 3.2 SROI of World Bank Projects 3.2.1 Purpose of the Cost-Benefit-Analysis 3.2.2 Indicators of the SROI Calculation 3.2.2.1 Net Present Value 3.2.2.2 Capital and Recurring Costs 3.2.2.3 Project Dates and Duration 3.2.2.4 NPV-horizon 3.2.2.5 Discount Rate 3.2.3 Types of NPV-Cost-Ratios 3.2.3.1 Pro-Rata-Capital-Costs Ratio 3.2.3.2 Total-Capital-Costs Ratio 3.2.3.3 Pro-Rata-Capital plus Recurring-Costs Ratio 3.2.3.4 Total-Capital plus Recurring-Costs Ratio 3.2.4 Calculation of the proper SROI Ratio 3.2.5 Portfolio Analysis 3.2.6 Sensitivity Analysis 3.3 Additional Economic and Financial Indicators 3.3.1 Economic Rate of Return 3.3.2 Benefit-Cost-Ratio 3.3.3 Net Benefit 3.3.4 Financial Net Present Value 3.3.5 Financial Rate of Return 4 Results of the Economic and Financial Analysis 4.1 Analysis Approach and Setup 4.2 NPV Outcomes at the Appraisal Stage 4.2.1 Appraisal NPVs of the LDCs 4.2.2 Appraisal NPV Continent Comparison 4.3 NPV Outcomes of the Result Stage 4.3.1 Result NPVs of the LDCs 4.3.2 Result NPV Continent Comparison 4.4 Appraisal vs. Result NPVs 4.4.1 Results of the LDCs 4.4.2 Continent Comparison 4.5 Economic Rate of Return Result Values 4.5.1 Results of the LDCs 4.5.2 Continent Comparison 4.6 Additional Economic and Financial Indicator Result Values 4.6.1 Benefit-Cost-Ratio and Net Benefit 4.6.2 Financial Net Present Value and Financial Rate of Return 4.7 Overall Project Performance 4.7.1 Definition 4.7.2 Overall Project Performance Ratings 4.7.3 Outcome Calculation for Non-Financial Indicator Projects 4.7.4 Verification of Outcomes and Conclusion 4.8 NPV-Cost-Ratios and SROI Calculation 4.8.1 NPV-Cost-Ratios of the ICR Reports 4.8.1.1 Overall Results 4.8.1.2 Continent Comparison 4.8.2 Standardized NPV-Cost-Ratios 4.8.2.1 Overall Results 4.8.2.2 Continent Comparison 4.8.3 Calculating the Minimum SROI Ratio 4.8.3.1 Overall Results of the Capital SROI Ratio 4.8.3.2 Continental Comparison of the Capital SROI Ratio 4.8.3.3 Overall Results of the Minimum SROI Ratio 4.8.3.4 Continental Comparison of the Minimum SROI Ratio 4.8.4 Making Meaning of the Results 4.9 Summary and Conclusion 5 Qualitative Data Analysis 5.1 Content Analysis 5.2 Sustainability 5.2.1 Sustainability Rating Definition 5.2.2 Sustainability Rating Categories 5.3 Bank Performance 5.3.1 Bank Performance Definition 5.3.2 Bank Performance Categories 5.4 Borrower Performance 5.4.1 Borrower Performance Definition 5.4.2 Borrower Performance Categories 6 Results of the Qualitative Data Analysis 6.1 Sustainability 6.1.1 Quantitative Assessment of Sustainability Ratings 6.1.2 Outcome of the Content Analysis 6.1.2.1 Types of Reasons 6.1.2.2 Overall Results 6.1.2.3 Results in Haiti 6.1.2.4 Continent Comparison 6.1.3 Excursus: Positive NPV Projects 6.1.4 Summary and Conclusion 6.2 Bank Performance 6.2.1 Quantitative Assessment of Bank Performance Ratings 6.2.2 Outcome of the Content Analysis 6.2.2.1 Types of Reasons 6.2.2.2 Overall Results 6.2.2.3 Results in Haiti 6.2.2.4 Continent Comparison 6.2.3 Summary and Conclusion 6.3 Borrower Performance 6.3.1 Quantitative Assessment of Borrower Performance Ratings 6.3.2 Outcome of the Content Analysis 6.3.2.1 Types of Reasons 6.3.2.2 Overall Results 6.3.2.3 Results in Haiti 6.3.2.4 Continent Comparison 6.3.3 Summary and Conclusion 7 Overall Summary and Conclusion 8 Critical Acclaim and Recommendations 9 Outlook and Future Research List of Appendices Appendix References