Cloud technologies are increasingly important for IT department for allowing them to concentrate on strategy as opposed to maintaining data centers; the biggest advantages of the cloud is the ability to share computing resources between multiple providers, especially hybrid clouds, in overcoming infrastructure limitations. User identity federation is considered as the second major risk in the cloud, and since business organizations use multiple cloud service providers, IT department faces a range of constraints. Multiple attempts to solve this problem have been suggested like federated Identity, which has a number of advantages, despite it suffering from challenges that are common in new technologies. The following paper tackles federated identity, its components, advantages, disadvantages, and then proposes a number of useful scenarios to manage identity in hybrid clouds infrastructure.