A private markets programme draws capital before it returns it. In the early years a fund calls capital and charges fees while its investments are still maturing, so the cumulative cash flow is negative before it turns positive, tracing the shape of a letter J. For a family office building a private markets programme, the J-curve is the central liquidity challenge: it must fund capital calls that are uneven and partly unpredictable, while distributions lag, and it must do so without holding so much idle cash that it drags the return or so little that it is caught short. This paper sets out a framework for managing the J-curve, the liquidity, and the commitment pacing of a family office private markets programme. It explains the J-curve and its causes, analyses the cash-flow profile of calls and distributions, develops a commitment-pacing model that smooths the programme across vintages, and addresses the denominator effect and allocation drift that complicate the build. It treats the liquidity buffers and over-commitment strategies that family offices use, the tools, including net-asset-value facilities and secondaries, that bridge and manage liquidity, the modelling that forecasts the cash flows, and the considerations specific to the GCC. The analysis finds that the J-curve is managed not by avoiding it but by pacing commitments across vintages to smooth it, sizing liquidity buffers to meet calls through a stress, and using financing tools to bridge, and that the family offices that manage it well build their programmes smoothly to target while those that manage it poorly face liquidity strain or allocation drift. Three family-office case studies, a sensitivity analysis, an international comparison and an implementation roadmap support the framework.