Our partnerships

Wolters Kluwer

Wolters Kluwer: the world's number one in software & services for tax and accounting. ADDISON has been part of Wolters Kluwer Software und Service GmbH since 2008.


Microsoft® is the world's leading manufacturer of operating system and application software. Our close Microsoft® partnership enables us to offer comprehensive support and up-to-date expertise.

CISCO Systems

When it comes to security, in addition to Microsoft solutions we rely chiefly on products developed by Cisco Systems, the leading provider of networking solutions for internet connectivity.


INFOLOG GmbH has been developing practical software systems for many years to reduce the workload of tax departments on a continuous basis. INFOLOG TAX SUITE handles demanding processes such as tax balance sheet preparation, e-balance sheet generation and tax audit workflows in their entirety.


ROSESOFT develops software for tax consultants, income tax assistance unions and tax departments. Our focus in on declaring and calculating personal and business taxes in compliance with the law as well as electronic communication with the fiscal authority.


Citrix Systems, Inc. is a leading provider of virtualisation technologies that enable businesses to deliver IT as an on-demand service. Citrix gained its reputation first and foremost with software and terminal server applications.

Kyocera Documents Solutions

Kyocera Mita Deutschland GmbH is a leading manufacturer of high-quality laser printers and digital copiers.


Protects your network infrastructure against internet threats such as hacking, spyware, viruses, phishing, spam and other malware from the web.

Citrix Xen Server

Management and integration of virtual infrastructures with Citrix XenServer software. Citrix offers unrivalled server consolidation solutions that increase IT security and reduce costs.

Ripe NCC Member

Ripe is a Regional Internet Registry (RIR) responsible for allocating IP address ranges and AS numbers in Europe, the Middle East and Central Asia.


The regify group is an international provider of trusted e-communications. regify's patented and data protection-tested technology allows for verifiable and legally compliant e-communication processes.


Plesk is a web server tool developed by Parallels Inc. for creating, securing and running websites and applications in the cloud.


HausPerfekt GmbH & Co. KG has firmly established itself on the market as a provider of highly specialised software for professional property management and property administration.