This document presents the results of an in-depth analysis of the drivers of cofinancing in IFAD-supported programmes/projects. The study covers 20 years of project-financing data from 559 projects in 109 countries. The analysis used rigorous statistical models, such as panel regression and sample selection models, to identify country-, project- and IFADspecific factors that trigger domestic and international cofinancing. In the first stage of the data analysis, the determinants of cofinancing committed at project approval were analysed to highlight the most significant drivers. In the second stage, cofinancing amounts disbursed at project completion were analysed to identify the underlying factors that explained the variations (positive or negative) between approved cofinancing amounts and the amounts disbursed. The analysis incorporated qualitative information on the challenges and opportunities of cofinancing, sourced from some regional economists, portfolio advisors and country programme managers. The findings corroborated the general decline in IFAD’s cofinancing ratios over recent decades, along with high variability during this time. Differences between regions in the distribution and structure of cofinancing were also observed. It appeared that donors’ initial commitment to IFAD-supported projects at the time of the design was not always definitive. For 131 projects analysed, 77 per cent reported a disbursed domestic cofinancing amount that was different from the appraisal amount, while 46 per cent had a disbursed international cofinancing amount different from the design figure. Among factors that predict the cofinancing level, country-specific conditions (such as income level, fragility, national budgetary limitations, quality of rural institutions, governance, the size of the country and its vulnerability) are significant determinants. Project characteristics are crucial for resource mobilization; in particular, larger projects attract more cofinancing than others. The quality of implementation is another project-related factor found to be a major driver of donor commitment throughout the project life cycle. Results also show that international financial institutions (IFIs) can have the flexibility to influence cofinancing in their supported projects by focusing on a number of factors under their control that have appeared to have significant effects on cofinancing. In IFAD’s case, for example, the in-country experience of country programme managers and the size of the portfolio they managed had significant positive effects on cofinancing. The presence of an IFAD Country Office also had a positive impact on resource mobilization. Furthermore, project partners’ perception of IFAD’s performance as a development partner of choice was a strong driver of cofinancing. It appears that the higher the IFAD performance rating is, the higher is the probability of an increase in the amount of cofinancing disbursed at completion.