He is survived by his loving wife of 52 years, Robbie Ray Parsons de Vries; daughter, Jessica Joan de Vries Kij and husband Jim Kij with granddaughter Kristen Alexandra Kij of Sugar Land; son, Dr. Peter de Vries of Houston; and sister, Dr. Swabina Thea Visser-de Vries of Holland. Born, raised and educated in Holland, Douwe was an avid tennis and hockey player, and learned at an early age to love classical music and play the cello. Prior to World War II, he served in the Dutch Merchant Marine. During the war, he took part in Dutch underground activities rescuing downed U.S. airmen, earning him several years in a German prison camp. After the war, he graduated from the eminent Technical University of Delft with an MSME degree. He was sent by Royal Dutch Shell to the U.S. and worked for 16 years for Shell Production and at Shell Development Co., developing air drilling, diamond bit drilling, floating drilling and completion technologies and becoming a U.S. citizen. Douwe established a consulting company in New Orleans and sold to Stewart & Stevenson in Houston, becoming Director of Engineering for its Oilfield Division, developing retrievable sub-sea control systems. Over the years, Douwe and Robbie made 42 trips to the Soviet Union for business and in his capacity as President of the Houston-Baku Sister City Association. After the sale of the Oilfield Division to NL Industries, he served NL Industries as Vice President in charge of sub-sea production. In 1981, he started Oilfield Systems Inc., specializing in design, manufacture and sales of proprietary oilfield equipment, automatic driller rental and consulting services for deepwater drilling/production. A Professional Engineer registered in Holland and Louisiana, Douwe consulted for oil companies worldwide and was recognized by both Shell and Stewart & Stevenson for his lifetime contributions to the development of floating drilling and production. The American Society of Mechanical Engineers awarded Douwe the prestigious ASME Holley Medal and made him an Honorary Member of ASME International, their highest award. He was inducted into the Oil Energy Center (OEC) Pioneer Engineering Technology Hall of Fame and Texas Gov. Rick Perry presented him a Certificate of Appreciation for 50 years as a Texas oil pioneer. He is an honorary member of the Council of American Master Mariners and a Presbyterian Elder. Douwe and his wife Robbie were members of Rice University's James A. Baker III Institute of Public Policy's Round Table. Douwe will be honored by the University of Houston's Cullen College of Engineering as the first inductee into its Hall of Fame, his books and papers will be accepted for their archives, and they will name their Dean's Conference Room in his memory.