X0206 3 2020-08-05 1 0001564406 Oak Street Health, Inc. OSH 0001782866 Newlight Partners LP 320 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0001820000 Newlight Harbour Point SPV LLC C/O NEWLIGHT PARTNERS LP 320 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0001782873 Newlight GP LLC C/O NEWLIGHT PARTNERS LP 320 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0001782860 Yadav Ravi C/O NEWLIGHT PARTNERS LP 320 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0001233188 WASSONG DAVID C/O NEWLIGHT PARTNERS LP 320 PARK AVENUE NEW YORK NY 10022 0 0 1 0 Exhibit 24 - Power of Attorney. This Form 3 is being filed by the Reporting Persons on the effective date of the initial public offering (the "IPO") of Oak Street Health, Inc. (the "Issuer"). Newlight Partners LP controls Newlight Harbour Point SPV ("SPV") and serves as the exclusive investment manager to its client in respect of shares held by SPV. The general partner of Newlight Partners LP is Newlight GP LLC (f/k/a Strategic Investments Group GP LLC). The sole members of Newlight GP LLC are Ravi Yadav and David Wassong. Each of Newlight GP LLC, Ravi Yadav and David Wassong disclaims beneficial ownership of the shares of common stock of the Issuer (the "Shares"), except to the extent of its pecuniary interest therein, and the inclusion of the Shares in any Section 16 report by such Reporting Persons shall not be deemed to be an admission of beneficial ownership of the Shares for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise. Information with respect to each of the Reporting Persons is given solely by such Reporting Person, and no Reporting Person has responsibility for the accuracy or completeness of information supplied by another Reporting Person. Managing Director of Newlight Harbour Point SPV LLC /s/ David Taylor, as attorney-in-fact 2020-08-05 Newlight Partners LP, By: Newlight GP, LLC, its general partner, /s/ David Taylor, as attorney-in-fact 2020-08-05 Newlight GP LLC, /s/ David Taylor, as attorney-in-fact 2020-08-05 /s/ David Taylor, as attorney-in-fact for Ravi Yadav 2020-08-05 /s/ David Taylor, as attorney-in-fact for David Wassong 2020-08-05