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Name organisation:
Gerlof Sijtsma
Organisation type:
Specialist software geared to (health) care, welfare and social services
Total Staff:
Information technology


AdSysCo has been a leading player in the area of ICT solutions socially for almost three decades, providing its services to customers in the overall area of (health) care, welfare and social services. It is with an integral ERP (Enterprise Resource Planning) solution that AdSysCo serves its customers, in which context it deploys on-line tools to grant access to members of the public (as its clients), network partners, volunteers and members of staff. AdSysCo’s sector-specific know-how in conjunction with its software and technology expertise places it in a class of its own.

We took Nico with us when we moved to AdSysCo in 2003

Gerlof Sijtsma and Nico Koppel have known one another for 20 years, as Gerlof explains: “Back then I held a number of director-cum-shareholderships. It was through a mutual business acquaintance – Doorneweerd’s pension consultancy, with whom Koppel shared a building – that we were brought into contact with one another. Until then I had always taken care of all the paperwork myself.” Gerlof recollects that when AdSysCo was launched in 2003 “we simply carried on our relationship with Koppel by taking them with us to our current business”

Koppel invests in lasting customer relationships, as Gerlof confirms: “We would have parted ways years ago had I been less than happy with Koppel, or Koppel with us for that matter.” A proactive approach and a keen understanding of the sector in which their customer operates ensure that their tax advice keeps matching the latest requirements.

Sorting out your taxes, that’s Nico’s forte

Gerlof: “There are certain services for which fiscally speaking it makes sense to have a tax consultant on tap. AdSysCo is made up of several economists, which makes us perfectly capable of seeing to our own accounts and preparing our own financial statements. The tax returns are a different matter. That and the payroll records and corresponding tax matters is where we rely on Koppel. Sorting out your taxes, that’s Nico’s forte.”

It’s super handy to have a single tax consultant take care of everything

AdSysCo operates several private limited-liability companies whose tax matters Koppel oversees. Says Gerlof: “Nico advises us not only on the set-up of the holding companies and the operating companies these straddle but on the shareholders’ personal holding companies as well, and takes care of our income tax returns and associated business. All in all it’s a fair bit of consultancy work!” He continues: “As director-cum-controlling shareholder you have to take the personal interests – such as personal holding companies – into account. Everything is intertwined and it all has to mesh, which makes it super handy to have a single tax consultant take care of everything.”

The old situation

It was 20 years ago that Gerlof Sijtsma – as the director-cum-controlling shareholder of a handful of businesses – decided the time had come for him to engage a tax consultant, to relieve him of the various accounting and tax duties he himself had taken care of until then. A business acquaintance referred him to Nico Koppel.

The solution

Koppel has been Gerlof’s expert sidekick ever since. AdSysCo in its current format is made up of a small group of economists, who are perfectly able themselves to take care of the accounting records and prepare their own financial statements. Koppel draws up airtight income tax returns as well as providing advice on the set-up of the holding companies and the operating companies these straddle, in addition to which it assists the various shareholders with the accounts of their personal holding companies and prepares and files their income tax returns.

The benefits

  • Proactive approach
  • Eagle-eyed
  • Both sector and niche specific know-how
  • Understanding of the complexities of a combined business and private holding company operation
  • Tax service expert

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