MWSS secured the approval from Civil Service Commission (CSC) of its Collective Negotiation Agreement (CNA) negotiated between the MWSS management and the MWSS Labor Association (MLA). The Certificate of Registration was released by the CSC on October 30, 2018 docketed as CNA no. 1503. The CNA, which has an effectivity period of 3 years from August 14, 2018 to August 13, 2021, underwent various revisions before the final version was approved by the CSC, pursuant to the Amended Rules and Regulations Governing the Exercise of Government Employees to Organize.