An investor in a PE fund whose liability is capped at its capital commitment and who does not participate in management. Typical institutional LPs: public pension plans (8-15% of total assets in PE), endowments (15-25%), foundations, insurance companies, sovereign wealth funds (e.g., GIC, ADIA, NBIM), family offices, and increasingly individual investors via interval funds and BDCs. LP economics are after management fees, fund expenses, and carried interest — the gross-to-net spread is typically 500-800 bps for a buyout fund (25% gross IRR → 17-20% net).