Because the plumbing and mechanical contracting sector is heavily fragmented and composed largely of private regional businesses, independent franchises, and commercial construction specialists, a single global corporate entity is difficult to crown as the absolute biggest. However, massive multinational facility management and mechanical engineering firms—such as EMCOR Group or Vinci—manage colossal commercial plumbing, HVAC, and infrastructure operations globally, generating billions of dollars in annual revenue across large-scale industrial and corporate projects.