IT Management and Subsidiary Companies

Hello,

I work as an IT Manager for a small organization that will in the near future have existing companies as Subsidiarys.

The companies which we will be acquiring currently have no IT management infrastructure in place.

I m wondering what should the IT relationship be between the parent and subsidiary companies.

What is the best way to manage IT for these newly acquired companies?

Are there any specific or standard policies and procedures which outlines a relationship between parent and subsidiary companies as far as IT is concerned?

Thanks in advance for all replies.

gtp