O-I
Oasen
Office Banen
OGD ict-diensten
OK
Omgevingsdienst Flevoland & Gooi en Vechtstreek (OFGV)
OnderwijsAdvies
Onderwijsselect
One-Time Recruit
Onjobs.nl
Option A d.o.o.
Optisport
Optiver
Organisation for the Prohibition of Chemical Weapons
Organon
OrganOx
ORO
OSVS
Otis College of Art and Design
OTTO Work Force
Oxford Global Resources
Oxford Instruments