Executive Interim Manager Siegfried Lettmann: Sales, Marketing, Product Management

About me

Since the early 90s I have been working as managing director, sales manager and division manager. Since 2012 I have been available to companies as Executive Interim Manager. I often work in international business areas and take care of business and organizational development for my clients, optimize processes and manage strategic sales initiatives, for example. In my mandates I focus on openness, transparency and clear values. I have a degree in business administration and have already received several awards for my work as an interim manager as a strategy and implementation expert. Born in Kiel, I now live in my adopted home of Salzburg. [more…]

>>> to my services offer

This is important to me…


Following my values, I lead according to the situation, taking into account my task, the specific company situation and the cultural circumstances. In doing so, I take a very goal-oriented approach, place emphasis on mutual trust, create clear responsibilities and thus unlock potential in the company. I ensure clear relationships and structures, promote order, give employees orientation and thus bring security into the company.

I have disciplinary management experience of up to 400 employees and have sales responsibility of up to EUR 700 million.



I invest in my further training – and thus also in your company. Because you benefit from the latest methods and expertise, which, coupled with my experience, can be transferred to you, your employees and your company in the long term.

You rightly expect that your interim manager is always up-to-date, masters modern instruments and tools and knows current developments in his field of expertise. This is exactly why regular further training is important to me: so that I can provide you with qualified and professional support. Every year I invest at least 10 days in intensive further training measures. Here is an excerpt:

  • 2019: Digitalization in Sales, Management Forum Starnberg (DE)

  • 2018: Certified Change Manager (PROSCI), Tiba Business School (DE)

  • 2017: Business Model Innovation, certified, RWTH Aachen (DE)

  • 2017: Certified Project Manager (PRINCE2), Axelos (DE)

  • 2016: International Turnaround Management, FH Kufstein (AT)

  • 2015: Certified Interim Executive (EBS), European Business School (DE)

  • 2015: Certified Management Consultant, Wirtschaftskammer Österreich (AT)


I have already received several awards for my interim management mandates, including Interim Manager of the Year 2018. The CONSTANTINUS Award is a business award that is presented to particularly good and successful consulting and interim management projects by a jury of several top-class business leaders. The CONSTANTINUS is awarded on a national, European and international (worldwide) level.

  • Interim Management Excellence Award of the DDIM Dachorganisation Deutsches Interim Management (2018) (DDIM – Association of German Interim Management)

  • Constantinus INTERNATIONAL: State winner Austria in the global round of the business award (2018)

  • Constantinus Österreich: Winner of the silver Constantinus Award for Austria (2018)

  • Award as Interim Manager of the Year by the Austrian Interim Management Association DÖIM (2018)

  • Constantinus Europe: Winner of the silver Constantinus European Award (2016)

  • Constantinus Europe: State Champion Austria (2016)

  • Constantinus Österreich: Winner of the silver Constantinus Award for Austria (2015)

Publications and Professional Articles

customer segment management

Reach the right customers with optimized value offers

SalesExcellence – Zeitschrift für Vertriebsmanagement, Nr. 11, Juli 2018, S. 33 ff.

One of the big questions in saturated markets: How do I differentiate my offer from the competition? One possibility is performance leadership, but you have to know exactly what customers want. A good customer segmentation is an indispensable tool… (German)

Article as PDF
Innovative business models Siegfried Lettmann

Ways to an innovative business model: Future strength through hybridization

Industrieanzeiger – Zeitschrift des Kompetenznetzwerkes der Industrie, Nr. 17, Juni 2018, S. 20 f.

Manufacturing companies benefit from hybrid business models. But in many cases they shy away from supplementing their actual offering with suitable, often digitally supporting services and thus moving closer to their customers… (German)

Article as PDF
Interim Manager Sales

Strategic corporate development: seizing opportunities with interim managers

Controller Magazin – Zeitschrift für Controlling-Praxis, Nr. 3, Mai/Juni 2018, S. 58 f.

Interim managers are independent managers who are appointed by the companies on a temporary basis. Above all smaller companies profit enormously from such assignments… (German)

Article as PDF
Zeitschrift für Organisationsentwicklung

Digitized: What now?

OrganisationsEntwicklung – Zeitschrift für  Unternehmensentwicklung und Change Management, Nr. 1, Januar 2018, S. 103 ff.

While there is often talk about how to digitize, there is also a question that is generally neglected: What challenges will companies have to overcome once the modern seven-league boot of digitization has been implemented?… (German)

Article as PDF
Ideen- und Innovationsmanagement

Innovation with Interim Management

Zeitschrift für Ideen- und Innovationsmanagement, Nr. 4, Dezember 2017, S. 141 ff.

How modern companies can drive innovation with external help
Innovative companies often count on external support. Interim management is one point of contact here: Temporary managers temporarily bring the required competencies and capacities into the company and thus support the development and implementation of complex challenges. Also in the field of innovation, interim management proves to be a target-oriented instrument… (German)

Article as PDF
Interim Manager Siegfried Lettmann on the subject of personnel recruitment

Interim Management: Personnel search made easy

Chefbüro – Business-Magazin für Führungskräfte, Nr. 3, Mai 2017, S. 42 ff.

The connection is so complex that it has not yet been shown flawlessly, yet everyone involved is aware that the right personnel is a decisive success factor. The right personnel at the right time, one is tempted to add… (German)

Article as PDF
The desire to innovate thanks to interim management

Passion for innovation thanks to interim management

Leadership Magazin für Österreichs Führungskräfte, Nr. 3, März 2017, S. 8 ff.

SMEs face a number of obstacles to their ability to innovate. There is often a lack of resources – both in terms of personnel and monetary resources. Interim management brings an uncomplicated and resource-conserving desire for innovation to companies… (German)

Article as PDF
Inteirm Management Magazine Siegfried Lettmann

Generation transition:
How Interim Managers Help Family Businesses through Difficult Times

Interim Management Magazin, Nr. 4, Dezember 2016, S. 34 f.

Handing over a family business to the next generation is a challenge for everyone involved. Interim managers can help to make the best and most productive use of this phase of change… (German)

Article as PDF