Financing from institutional investors will be critical to achieving the sustainable development goals and curbing climate change. However, these large investors have been largely absent from multilateral initiatives to mobilise private capital. Partly as a result, such initiatives have been unable to reach the scale required for development finance to go “from billions to trillions”. Successful mobilisation of private capital – including from institutional investors – has instead frequently taken place at the local level, by strategic investment funds and some green banks. At the same time, some institutional investors have been changing their modus operandi, from an intermediary to a collaborative model, and are re-localising their operations. The elimination of financial intermediaries with a short-term focus removes a bottleneck between two categories of long-term investors – institutional investors and multilateral finance institutions. That opens new opportunities for collaboration, as discussed in this paper.