Individual agreement between an LP and the GP modifying the default LPA terms for that LP — the primary mechanism by which large or strategic LPs extract economic concessions, governance rights, or reporting enhancements beyond the LPA's baseline. Commonly negotiated terms: management-fee discounts (5-25 bps below base), accelerated step-downs, enhanced fee offsets (100% vs. 80%), carry discounts (17.5-18% vs. 20%), higher hurdle (9-10% vs. 8%), modified catch-up (50/50 vs. 100%), priority co-investment rights, key-person enhancements, LPAC seats, customized ESG and underlying-portfolio-company reporting. LP negotiating leverage scales with commitment size, anchor status, relationship history, and brand (CalPERS, Harvard, Yale command extensive modifications).