Choke Point by Ridley Pearson

A high-testosterone thriller in a series featuring John Knox as an operative/heavy and Grace Chu as computer hacker for a private security firm.  This time they are trying to find and dismantle a 'knot shop' in Amsterdam, which employs and enslaves young girls to keep labor costs low.  Plenty of intrigue, chase scenes and combat ensue as the pair lures the 'knot shop' owners out of the shadows.  399 pages.