Calland graduated from the United States Naval Academy with a Bachelor of Science degree in 1974 and subsequently graduated from Basic Underwater Demolition/SEAL Training (&lt;a href="BUD/S"&gt;BUD/S&lt;/a&gt;) class 82 in 1975. Calland served as a Platoon Commander of a SEAL Delivery Vehicle (SDV) platoon and a SEAL Platoon, Instructor BUD/S Training and Naval Special Warfare/Explosive Ordnance Disposal Officer. Calland served as assault group leader with SEAL Team SIX followed by assignment as executive officer of Special Boat Unit 12 in 1987. He deployed as part of Operation Earnest Will in the Persian Gulf. Calland took command of SEAL Team ONE from November 1992 until January 1995. He later went on to receive a Master of Science degree in national resource strategy from the Industrial College of the Armed Forces in 1996. From June 1997 until June 1999, Calland commanded the Naval Special Warfare Development Group. Calland was the commanding officer of Special Operations Command Central (SOCCENT), part of United States Central Command, and as such, commanded efforts in Afghanistan in 2001 during Operation Enduring Freedom. Between August 2002 and March 2004, Calland served as the commanding officer of the Naval Special Warfare Command.