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The process goes something like this:
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From the ordering user
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's perspective
1. When Order Approvals is enabled for a Customer account, during Checkout, a popup message alerts the ordering user that approval is required as the order is over their order limit:
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4. The user can view their 'pending approval' orders as well as any that have been rejected in Order History (Dashboard → Order History). Note - approved orders will move to the next stage of the usual order processing procedure. 
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From the Approver
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's perspective
An approver is another user on the Customer account. When an approver has been assigned to an order, they will receive a notification email. If Approve/Reject links in this email have been enabled, the Approver can simply click on the relevant link depending on their decision:
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The Approver can view 'pending approval' orders requiring their decision through the Approve Orders function available on their Dashboard.
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See Order Approver Functions for guidance on approving orders.
Order Approval Modes
There are three Order Approval modes that can be set:
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