The Independent Evaluation Group (IEG) will conduct a focused assessment of the Private Sector Window (PSW) of the International Development Association (IDA). The assessment will update a previous IEG evaluation of the PSW and complement a concurrent paper by IDA, the International Finance Corporation (IFC), and the Multilateral Investment Guarantee Agency (MIGA). This focused assessment (the PSW evaluation update) responds to a request by the Committee on Development Effectiveness and World Bank Group management for IEG to prepare an update to The World Bank Group’s Experience with the IDA Private Sector Window: An Early-Stage Assessment (World Bank 2021), which was completed by IEG in July 2021 and covered the PSW implementation experience under the 18th Replenishment of IDA (IDA18) for fiscal years 2018–20. The PSW evaluation update will add IDA19 and early IDA20 PSW projects. Concurrently, IDA, IFC, and MIGA are jointly preparing a paper on the PSW as an input to the IDA20 Mid-Term Review, focused on implementation progress and early results of the PSW (the IDA PSW paper). The IEG and IDA-IFC-MIGA teams working on the two assessments have agreed to conduct complementary analyses to inform the Mid-Term Review.