Project production comprises a cycle of strategy development, identification, preparation, appraisal and executive board approval, implementation, supervision and completion, followed by evaluation.<sup>2</sup> There are numerous contributors at each stage. On the World Bank side, strategy development is the responsibility of the country management unit, in particular the country director who determines the size of the financing envelope; project preparation, appraisal, supervision and completion are largely the responsibility of the task team, comprising technical and fiduciary specialists, but with guidance from sector managers and country office representatives. To the extent that previous studies have estimated the impact of individual professionals, this has largely been limited to the project manager (commonly referred to as Task Team Leaders or TTLs in the World Bank) during project implementation. Almost none have identified or attempted to measure the contribution of other participants in the process.

Along these lines, one contribution of this study is to more comprehensively assess the contribution of project design and supervision to development effectiveness. We consider the usual explanatory factors of project level success in the literature, clustered around (i) country characteristics, such as institutional quality, political and economic stability, and economic growth trajectories; and (ii) project characteristics, such as duration, size, sector and lending instrument. Additionally, we include (iii) aspects of project design, such as the clarity of results frameworks, the number of components, and the characteristics of staff involved in design and (iv) aspects of project supervision, such as the intensity, quality, and continuity of oversight. For this, we combine data on World Bank projects’ outcomes with a novel data set derived from project preparation documents and internal staff records. Specifically, we examine the contributions of the TTL who prepared the project, the Practice Manager who oversaw them and the Country Director responsible for the country program within which the project was set, as well as the chain of TTLs who supervised the project until close.

A second contribution of this study is to examine measures of project quality as captured in original project documents. For a stratified random sample of 120 projects, we manually extract detailed information from primary project documents, including an expert panel assessment of the design quality and a thorough review of evaluation reports from outlier projects – defined either as those with highly satisfactory outcome ratings in low capacity environments (‘positive outliers’) or highly unsatisfactory ratings in high capacity environments (‘negative outliers’). These harder to measure aspects of project design and supervision comprise support for center-of-government functions such as planning and budgeting, human resource management, financial management and procurement; and support for strengthening the implementation capacity of sector agencies, such as through results-based management. In theory, their effect may be felt not just on the management of interventions financed by the project but through institutional spillovers to other areas of government activity.

The project cycle is similarly complex on the government side. Responsibility for advising on the content of the World Bank’s strategy and identifying projects lies with key economic ministries, typically finance, planning and investment, and sometimes international cooperative bodies. Investment projects are generally implemented by line ministries or, in some cases, specialized government agencies. There are also operations implemented by sub-national governments, either states, provinces or municipalities, whose capacity can substantially vary. In each case, direct responsibility typically lies with a project implementation unit, staffed with civil servants who may or may not have previous experience of World Bank projects. All investment projects also depend to a greater or lesser degree on the effectiveness of

> 2 See Figure A3.1 in Annex 3 for a schematic representation of this process, as detailed in World Bank (2011).

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