***Naval Information Warfare Center (NIWC) Atlantic requires support for ESS Sustainment. This DRAFT RFP N6523626RE026 is an opportunity for industry to review a DRAFT Performance Work Statement (PWS), Section L, and Section M prior to the formal issuance of the RFP which will be solicited as unrestricted. The Government contemplates award of a performance-based, Firm-Fixed-Price, Cost-Plus-Fixed-Fee, Level-of-Effort, and Cost task order for a base period of 1 year plus 4 one-year option periods, and 1 six-month option period. The Government anticipates issuance of the RFP in June 2026 and award by August 2026. NOTE: the PWS, Section L, and Section M documents are DRAFTS and therefore, subject to change.*** ***This opportunity is for SEAPORT NXG MAC HOLDERS ONLY. No other offers will be considered. SeaPort MAC holders will need to register for PIEE accounts in order to receive solicitations and submit proposals/offers in response to the official RFP.*** ***The contractors will be tasked to accomplish the work as specified in the Performance Work Statement (PWS). The PWS includes Controlled Unclassified Information (CUI) and will not be made publicly available. In order to obtain access to the PWS, the offeror shall download, complete, and submit a signed Non-Disclosure Agreement (NDA) for each individual requiring access to the non-public documents to Mindy Odenkirk, melinda.k.odenkirk.civ@us.navy.mil.***