Maceira Zayas advises on public-private partnerships under Act 29-2009, the statute that created the Puerto Rico Public-Private Partnerships Authority (P3 Authority) and governs how the Commonwealth structures, procures, and awards P3 projects. The firm's work spans the project lifecycle: feasibility and structuring, the P3 Authority's procurement process, desirability and convenience studies, contract negotiation, financing, and post-closing compliance.

The practice draws on experience from both sides of the table. Anthony O. Maceira served as a director of the Puerto Rico Ports Authority during the San Juan cruise piers and Maritime Transportation Authority ferries transactions. As consultants to the P3 Authority, Maceira, Jorge Alexis Meléndez Rivera, and Crystal N. Acevedo-Jiménez worked on creating the Authority's Third-Party Procurement Office (3PPO) and the procurement manuals for the LUMA Energy and Genera PR transactions, which selected the operators of Puerto Rico's electric transmission and generation systems. The firm has advised Genera PR on matters arising under its public-private partnership agreements. Matters handled by the team exceed $600 million in infrastructure value.

Infrastructure in Puerto Rico runs on federal money, and the firm practices accordingly: FEMA Public Assistance and HUD CDBG-DR funding rules, procurement under 2 C.F.R. Part 200, Build America, Buy America compliance for federally funded projects, and coordination with federal agencies from the FAA to the U.S. Army Corps of Engineers. Maceira Zayas (MZLS) advises P3 sponsors and public entities with offices in San Juan and Washington, D.C.