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Lead may be assigned to a user, either yourself or another user, from within Lead Liaison. When a lead is assigned to a user other than yourself an email will be sent to the recipient. The email provides a summary of the lead's online behavior along with their most recent activity history. When a lead is assigned, either to yourself or another user, a +1 is added to the Alert Center and a message is added to the recipient's inbox.
To assign a lead to someone change the lead owner. See the Lead Ownership section for more information on how to change the lead owner.