Postmarks are the pen marks, handstamps and machine cancellations used to deface stamps carrying mail.  The uniqueness of the postmarks applied to a common cover can increase it's value to the collector.  Looking for specific postmarks can add to the excitement of philately.

• First Scout Cancellations by Country HTML 101K WORD97 113K
• Designing and Obtaining US Cancels
• U.S. Precancel Scout Stamps
• U.S. Scout Bullseye Cancels
• Collect Something Else - Historical Date Cancellations
• U.S. Mailers Postmark Permit

• 1935 US Boy Scout Cancellations
• The Precancel Stamp Society
• Post Mark Collectors Club
• Postmark Collecting Preferences
• Texas Precancel Club
• Bullseye Cancel Collector's Club
• Mailer's Postmark Permit Club
• Your Own Mailer's Postmark