This site is built using the free open source Drupal and CiviCRM software. These are under constant development, and occasionally we need to install a significant upgrade to keep pace with the latest versions. This is a requirement for maintaining security of the site, and typically also adds many new features and improvements. Today we have committed a (some might say brave!) double upgrade: from Drupal 4.7 to Drupal 5.1, and from CiviCRM 1.5 to CiviCRM 1.7.