Most global CRO are corporate entities. Global capabilities exist because they have regional and offshore office in many countries.
Instead establishing office in many countries, which is cost enormous investment, establishing alliance with local CRO seem more realistic and have many advantages. Business alliance with local CRO creates global networks, where sponsor have the flexibility to pick and choose the regions or services they desire.
Local CRO has knowledge of the regulatory and guidelines, has strong relationship with investigator and physicians, establish networking with local clinical research centre, and supported by enough resources (including workforce and financial). In other word, local CRO understand how to conduct clinical trial in a particular region.
CRO 
