Singer describes three categories of privatized military systems. "Provider firms" (the best known being the now reorganized Executive Outcomes) offer direct, tactical military assistance ranging from training programs and staff services to front-line combat. "Consulting firms," like the U.S.-based Military Professional Resources Inc., draw primarily on retired senior officers to provide strategic and administrative expertise on a contract basis. The ties of such groups to their country of origin, Singer finds, can be expected to weaken as markets become more cosmopolitan. Finally, the overlooked "support firms," like Brown & Root, provide logistic and maintenance services to armed forces preferring (or constrained by budgetary factors) to concentrate their own energies on combat. Singer takes pains to establish the improvements in capability and effectiveness privatization allows, ranging from saving money to reducing human suffering by ending small-scale conflicts.