Abstract: An extendable-length, spine immobilizing backboard is disclosed. The backboard is collapsible to the length of a standard backboard for ease of storage and for use in supporting and transporting patients of average height, and a lower portion is telescopically extendable from an upper portion so as to adjustably accommodate patients of above average height. The upper and lower portions are joined by side shafts that telescopically insert into hollow tubes so as to form hand rails on either side of the backboard, and by a flat, rigid central extension that is slidably insertable into a central cavity so as to provide patient support across a gap between the upper and lower portions. The backboard can be collapsed to a length that is six feet, and extended to a length of eighty inches. In some embodiments, the backboard is wider than a standard backboard, being preferably 21 inches wide.