Siers & Collegen GmbH


Implementing strategies successfully


Exploiting chances of change management optimally


We are on fire for your corporate culture


Change of philosophy in sales



If you interlink structure and corporate culture, you will be more successful

… because you will create the basis to implement strategies optimally. That is what we are specialists for – Siers & Collegen.
Processes and tools give your managers and staff orientation. Thus, the structure provides the necessary guide rails. And your corporate culture? It is the deciding factor for the implementation in practice. Without a suitable corporate culture: no implementation. Values such as liability, transparent communication and role model function of the managers are relevant parameters. Both – structure and culture – are not to stay soloists in your company. We join them effectively and, thus, increase your success.

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Meet Siers & Collegen

Carsten Siers provides you with insights into the sustainable implementation competence of his team.

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About us

We are authentic

Get to know our team of specialists

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Druckfrisch. Die 8. Studie Vertriebskompass 2017/2018

Carried out by the technical college of Aachen in co-operation with Siers & Collegen

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Thats what our customers say

The long-standing co-operation with the sales consultant Siers & Collegen has always been very partner-like and goal-oriented. Especially outstanding with the team of Siers & Collegen is the high implementation competence, whether it be by means of the conception of pragmatic sales guide rails, the qualification of managers & staff or the development of the corporate culture. At large, this has helped us deal with our markets more efficiently nowadays.

Frank Koch, Chairman of the Board

The joint project with Siers & Collegen helped us considerably, not only to obtain a clear picture of the status quo of our corporate culture but also to create clear common (also cross-sectoral) goals and a resulting interaction on this basis which characterizes and simplifies the common daily co-operation. The transparent and, above all, pragmatic approach is of practical benefit for us so as to achieve change and advance it in a focused way.

Thomas Schmidt, Chairman of the Board
ENTEGA Energie GmbH

We have been co-operating with Siers & Collegen for several years. The clear focus on implementation of Siers & Collegen helped us implement our sales concepts on the market optimally. In addition, it was decisive that the managers were developed into implementation multipliers and, thus, promote the change process optimally.

Martin Metzler, Head of Sales Bath & Wellness EMEA (Europe, Middle East, Africa)
Villeroy & Boch

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