You can import Clients into SI from Microsoft Outlook. Outlook should be open prior to importing Clients. This is not required but speed will be improved.
There are filters in the ribbon for showing All, New, or Matched Clients. The New filter shows only Clients who don't already exist in SI. The Matched filter will shows only Clients that already exist in SI, use this for updating information for existing Clients. There are column filters and a search field as well. You can also choose a specific Contact Folder from Outlook.
Select an available Address Type from Outlook to import as the Billing and Site Address. You can also choose if you want to "Import Company Name as Client Name":