Technology is disclosed for providing contact management services. Contact information (e.g., phone numbers, addresses, email addresses, etc.) are collected from multiple, different sources (e.g., a mobile phone, a web server, a social media web site, SMS, an App, etc.) Contact information can also be entered in a free-form format and parsed into structured data that is associated with a contact card. A contact card stores the contact information and the source of the information. Contact cards can be aggregated into a merged contact card that includes information from the multiple, different sources, without loosing the original information. The merged contact card can be disaggregated into its constituent contact cards and used to create other contact cards. A user can associate one or more of their contact cards with a group. The group is optionally notified when the users changes its contact information.