Köster Advocaten is part of an international network of law firms, called LEGUS. Köster Advocaten also works closely with variousindustry associations.

LEGUS is an international network of independent law firmswith offices in all EU countries, almost all U.S. states,Central and South America, and with offices in SouthAfrica, India and the Far East. For all cases in whichexpertise from offices abroad need to be enabledmembers of the network, guaranteeing quality and speed.

 First Formula
First Formula BV is the publisher of The National Franchise & Formula Guide. We specialize in products and services that bring the franchise market and the retail market clearly map. The aim is to bring. Different players in the franchise / retail in contact with each.

SportSupport Haarlem
Köster Advocaten is a partner of Sport Support Haarlem, an organization in and around Haarlem is active in providing information, advice, organization and support of the sport.

Köster Advocaten is a partner of the Royal Dutch Baseball and Softball Association and advises the KNBSB and associations affiliated to the union in legal matters in the area of ​​sports law.

Associatie Nederlandse Tandartsen
The ANT is a professional association of dentists, established in 1995 On July 5, 2002, the Minister of Health ANT designated "representative organization" for dentists and dental specialists. 

The ABU (General Association of Temporary Employment Agencies) is the interests of the broadcasting companies in the Netherlands. With over 360 members, the sector represents more than 65 percent of the market and is the largest employers' organization within the staffing industry. Together realize the ABU members per year more than 325 million hours of broadcasting, which they not only help hundreds of thousands of temporary employees to work and work experience, but also help thousands of companies to flexible workforce.

ABU Legal
ABU Legal is the legal services branch of the General Union Agencies (ABU). The individual services are provided by Köster lawyers. We combine our specialization in the various jurisdictions in which the employment agency has to compete with a thorough knowledge of the staffing industry and its specific laws and regulations.

De Vereniging Payroll Ondernemingen
The Association of Payroll Association (FPA), founded in September 2006, is the trade association that represents the interests of payroll companies. The VPA is committed to increasing the social recognition of the product rolling. An important tool here is the VPO membership as the ultimate mark of quality within the payroll industry. A member of the VPO payroll company clients are not at risk. Members of the FPA are checked for proper application of the Employment Regulations, the quality of the administrative processes, timely payment of taxes and social contributions and a solid business.

VPO Legal
VPO provides to its member companies payroll legal services under the name VPO Legal. This service is performed by Köster Advocaten. Our practice group staffing industry is fully focused on all forms of flexible employment, including payroll. Moreover, our knowledge of the industry and the prevailing laws and regulations kept up-to-date, because we also advise VPO themselves and are closely involved in the design of the Employment Regulations.