At IEG, we’re often asked “Why do some World Bank projects succeed, while others fail?” Dozens of development professionals, academics, and researchers have struggled with this question, and their answers are complex. There are so many critical factors and variables that might have a positive, negative, or neutral association with project performance; and not everyone agrees on which factors matter most.  

In the recent annual review of Results and Performance of the World Bank Group (RAP17), we conducted a structured literature review to find out which factors associated with better and worse project outcomes have garnered the most consensus among researchers. 

Starting with 122 sources, we narrowed the list down to 32 studies that included an empirical analysis of World Bank project outcomes and were published either by the World Bank or a peer-reviewed journal. There was considerable variation in the methodologies of the studies included, and while this has advantages in maximizing the kinds of factors that can be captured in this review, it also reduces the validity of comparing across studies. As such, we do not make any claims about the relative importance of any individual factors.

We instead grouped the factors into three broad categories:

Country-level factors Political economy-level factors Project-level factors

Elements of a country’s economic and socio-political environment that may influence project outcomes. Examples: economic conditions, human development measures, conflict and fragility, environment, and macroeconomic management and policies.

Elements related to the incentives and interactions between borrowers and donors in selecting and executing successful projects. Examples: alignment of donor and recipient objectives; a conducive policy environment; natural resource dependence.

Characteristics or elements of project preparation and supervision that are plausibly within the control of the World Bank. Examples: quality of design, supervision effort, M&E capacity, task team leader (TTL) and team characteristics.

To present these factors, we created an interactive tool to map the factors that studies found to be associated with higher or lower project outcomes. In the visualization below, each shape represents a factor studied. These factors (shapes) are grouped according to the categories above (country-level, political economy-level, project-level) and the direction of that factor’s association with project outcome. Factors in blue are associated with successful projects, while those in orange are associated with unsuccessful projects. The darker the blue or orange, the more consensus there is in the literature about the positive or negative direction of the association. The larger the icon, the more sources discuss it as a factor. Grey icons represent factors for which the literature found either mixed or neutral effects.



Political economy-level


Color color_scale_1.jpg
Size  The larger the icon, the more sources discuss it as a factor.
Instructions Hover your cursor over any of the icons to see the factor, its category, and a brief description of the concept. If you click on the factor, you can filter the list to show only the studies with relevant findings, along with their assessment of whether it has a positive, negative, or neutral association with World Bank project outcomes. Click on the reference to open the study reviewed in a new browser window.

At the country level (keeping in mind the caveat that we do not make claims about relative importance), the most commonly identified success factor was economic growth, while project success is less likely in fragile and conflict-affected situations (FCS) and when civil liberties protections are limited. At the project level, supervision quality and the task team leader’s track record were commonly identified project success factors. Other success factors included incorporation of lessons learned and analytical work, the quality of the project’s results chain, and the overall quality of project design. But many other factors were also identified.

We hope that this interactive tool can enable you to discover new research, and inspire more thought-provoking studies into development project outcomes. We invite your feedback on this tool and how it might prove useful to your own work. What studies have you found helpful?  What insights did you find most surprising? Please let us know in the comments.  

To read more about our methodology and findings, please see Appendix H of RAP17.



Interesting, but makes me wonder again about the quantitative bias of donors. If not statistically valid = throw away. Basically as research agenda is quasi-academic, notably by journal producing academics who set the tone. Alternative: learn from what private sector marketing firms do = much use of representative FGDs. In this case, FGDs of persons experienced in implementing projects (private firm people and donor people). Of course biases, and some products flop despite favourable FGD research, so we quasi-academics conclude that marketing people just "have it all wrong"? We should be more humble, after all they knew about irrational man decades before we discovered experimental economics.


There is a preliminary question that in our view should be answered: A successful Project for who? There are different actors around a project: Stakeholders, Governments, Communities. whose objectives, interests, expectations aren’t necessarily the same and therefore there is a continuing negotiations to reach a common agreement.
Moreover, there is a fourth factor to make it a successful Project, namely the experience and expertise of the Team in charge to run the field operations on the grounds that they have to translate into practice above-mentioned factors and find out a welding point to a get a shared consensus among the Actors. This does mean that the Project Leader should have experience and expertise in the Project related matters well above the ground.
Assuming that a Project should serve the Community, there is a wide consensus on the core business of whatsoever intervention: sustainability for the providers, affordability for the beneficiaries, transparency of the interventions along with a tangible impact on the related communities.
How to translate in the field activity the proposed approach? In our just released eBook, we have made a further step ahead and tried to answer to the question: “The Gateway to Africa Inclusive Growth – JAMBO FUND”….
Actually it is a feasibility study, which is a suitable approach to make it happen poverty mitigation and countries’ economy growth via job creation and people empowerment. Although the Continent is the reference (it was necessary to have a landscape to refer to) the Model is suitable at region and country level world-wide. Moreover, the study provides the MODEL for a business plan: it is just a matter to apply the proposed methodology.
However, JAMBO isn’t just financing but much more: it is a new way to approach the market. In particular, we elaborated on both the Basel III Committee Document on Financial Inclusion and the Goal 8 of UN 2030 Agenda: “Promote inclusive and sustainable growth”. It is worthwhile to note that in the wave of digitalization, the proposed approach is of utmost importance because the basic question isn’t to provide people with a smart Mobile phone or WhatsApp but to have people eligible for its use. Under the particular circumstances, the methodology will guide the interventions in the emerging economies with a well-defined algorithm and appropriate market segmentation, as it has been visualised in the Slide – letters c and d -, which explains the methodology behind the Project.


I would like to cite this study, particularly the negative impact of (presumably) negative human capital. Is this study disclosed or disclosable?

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