During the multi-national "Joint Task Force Exercise/Theatre Missile Defence Initiative 1999" (JTFEX/TMDI99) Walrus successfully penetrated the U.S. Navy screen and "sank" several ships, including the aircraft carrier USS Theodore Roosevelt before escaping.

In September 2000 all four Walrus-class boats were withdrawn from service after micro-fractures and corrosion was detected in the diesel engine exhaust valves.

From September to December 2002 Walrus took part in "Operation Enduring Freedom", acting as an COMINT intelligence gathering post in the Arabian Sea and the Persian Gulf.

[2][3] In 2007 she took part in exercises in the Caribbean Sea with special forces of the Netherlands Marine Corps.

Walrus was to be the last of the class to undergo refit and upgrade and was scheduled to return to operational service in 2019.