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For Interim Manager
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Satisfied Customer Voices

Feedback from companies and candidates – because success for us is when both sides win.
COO aus Österreich
Energiekonzern in AT
"After a bumpy ERP go-live and a gap in the leadership team, we urgently needed interim management. Armin Rainer understood the situation immediately and delivered a tailor-made interim solution within a few days: a stabilization plan, stringent stakeholder management, and hands-on on-site support. A few targeted measures ensured rapid stabilization. We were particularly impressed by the honest expectation management, clean reporting, and zero hidden costs. We would do it exactly the same way again."
Alessandro Ranzoni
CEO Häny Gruppe, Jona
"In a phase of strategic realignment, the change in management of the Austrian subsidiary was a decisive step. The placed interim manager brought clarity, pace, and a high degree of leadership from day one. The collaboration is professional, transparent, effective, and built on genuine trust."
Robert Bermoser
Interim Manager (Geschäftsführung)
"What began as a temporary interim management (~6 months) became an eight-month structural realignment of Häny Austria GmbH, including process adjustments – demanding both professionally and personally, and always with a focus on the human factor. Particularly positive: the recruitment of the new Managing Director – meticulously aligned with the requirements profile, convincing in both expertise and character, with a sustainable perspective for the Group. The regular, open feedback sessions demonstrated lived customer orientation. I am very happy to stay in touch and am available for future mandates."
Paul J.
Interim General Manager
"Mr. Rainer clearly stands out from the headhunters I have been in contact with so far. The support he provided before, during, and after the interviews was very valuable to me. In particular, the concrete feedback on the course of the conversation, combined with the preparation for the next interview, I rate as outstanding in its professionalism."
Jann Dittmann
Interim Manager (Projektleitung)
"The project was originally planned for 7 months but ended up running for 16 – because the collaboration worked excellently in a complex customer situation. Despite multiple, sometimes short-term changes in course, the analysis, communication, and expectation management remained clear. The goal: stabilization and efficiency without unrest – achieved. Billing was smooth and punctual. From today's perspective, a follow-up project is realistic; I would very much enjoy working with Armin Rainer and Kai Becker again."
COO aus Österreich
Energiekonzern in AT
"After a bumpy ERP go-live and a gap in the leadership team, we urgently needed interim management. Armin Rainer understood the situation immediately and delivered a tailor-made interim solution within a few days: a stabilization plan, stringent stakeholder management, and hands-on on-site support. A few targeted measures ensured rapid stabilization. We were particularly impressed by the honest expectation management, clean reporting, and zero hidden costs. We would do it exactly the same way again."
Alessandro Ranzoni
CEO Häny Gruppe, Jona
"In a phase of strategic realignment, the change in management of the Austrian subsidiary was a decisive step. The placed interim manager brought clarity, pace, and a high degree of leadership from day one. The collaboration is professional, transparent, effective, and built on genuine trust."
Every day counts. Let’s start today. Book your free consultation now:
Find Manager – in 1 Week
Free initial consultation
Use Cases

Our Offer

And how we can support you in your individual situation

Fill vacancies

One of your top executives is unexpectedly unavailable, whether due to illness, accident, dismissal, or parental leave. You neither want to return to day-to-day operations yourself nor overtax the remaining leadership. Bring an experienced interim manager to your side who will take over the position quickly and competently.

Implement projects

Your leadership crew manages the day-to-day business successfully, but a special strategic project lies outside their core competencies. Whether it is a change of location, a product launch, or a new ERP system – provide your team with a specialist who has already successfully handled such projects multiple times.

Shape change

For the digitalization of your business model, you need new thinking and external expertise. Get an experienced change expert on board who, together with your management, plans and implements the transformation project and takes responsibility for its successful completion.

Case Study: A company loses its CFO at short notice

Problem: Reporting collapses, banks demand clarity, management is flying blind. How we help: An experienced CFO stabilizes liquidity, establishes weekly reporting, and creates transparency for owners and the leadership team within a few days. The organization regains security – until the permanent replacement takes over.

Case Study: ERP implementation project threatens to fail

Problem: Milestones are missed, internal teams are at capacity, the implementation is losing structure. How we help: We provide an interim project manager with ERP experience who reorganizes the project, sets clear responsibilities, and steers the implementation with a high cadence. After a few weeks, the project is back on track – and goes live successfully.

Case Study: Growing company must make structures fit

Problem: Responsibilities are unclear, decisions take too long, teams are working at cross-purposes. How we help: An interim change manager accompanies the transformation: they create role and process clarity, establish a functioning leadership routine, and anchor new behavior in day-to-day operations. After a short time, the organization is noticeably more stable, faster, and better coordinated.
Do you recognize parallels – or are other topics currently on your mind? Let's talk.
Find Pro – in 1 Week
Free initial consultation
Process

Our Workflow

Thats how we collaborate with you
Zwei Personen in Hemden schütteln sich die Hände über einem Tisch mit Laptop und Klemmbrett.
1

Situation Analysis

In a max. 90-minute situation analysis, we jointly define the need for experience and specialized knowledge for your company. Here, we draw on an enormous wealth of experience to precisely and quickly identify which qualities your interim manager must bring.
2

Presentation of Top Candidates

Within a few working days, you will receive 2-3 profiles of suitable interim candidates from us and choose whom you invite for an initial interview. We coordinate and accompany the entire process and advise you following the interviews.
3

Prompt Start

You decide which candidate fits your company best. We take care of the contracts and ensure a prompt start. Our fee is based without exception on the days worked by your interim manager in the following month, according to the performance record approved by you.
Let’s talk about your possibilities. Book your free and non-binding initial consultation now:
Find Expert – in 1 Week
Free initial consultation

We support you with a lot of experience

1500+
Placings per year
800+
Partners & employees in D/A/CH and worldwide
100 Mio.+
Revenue per year
60+
Locations & offices in D/A/CH and worldwide
The Invest
Interim Management is too expensive for you, you say?
We see it rather as an [investment that pays off].
In the UK, Benelux, and Germany, interim management has long been a common model for the temporary reinforcement of existing management teams and for increasing the success of numerous companies – with a positive ROI. Many companies in Austria initially question the financial expenditure for interim management. We at ISG understand this reluctance and meet it with complete transparency. Therefore, together with you, we analyze the actual and hidden costs of unfilled positions and contrast these with a professional interim solution. Free of charge and completely non-binding. Our decades of experience from hundreds of projects in a wide variety of industries confirm time and again:
Usually, specialized expertise pays off [from day 1].

Find specialist – in 1 Week
Free initial consultation
Our philosophy

ISG stand for...

Our Promise

We fill your position within 1 week. And thereby help to secure your goals and the success of your company in the long term.

Our Drive

Developing the best solution for your company in your individual situation – together with you.

Our Background

For 25 years, we have been solving critical situations in decisive moments of corporate history.
Das Team

ISG International Service Group


Managing Partner

Dipl.-Ing. Armin W. Rainer

I help entrepreneurs with the staffing of their top leadership teams. From 20+ years of management experience, I know exactly what it feels like to carry responsibility and to secure sustainable corporate success.

My Expertise

  • 20+ years of leadership experience in family-owned businesses and publicly listed corporations
  • ISO-certified Executive Coach, specialist trainer, and registered mediator
  • Successes as an employed manager and independent entrepreneur
  • Embedded in ISG with access to a powerful network of specialists

My Approach

Based on my practical knowledge, I work with you to very quickly grasp the core of your problem and develop accurate strategies for sustainable solutions. As an ambitious road cyclist and passionate offshore sailor, I am well acquainted with shifting limits of endurance and the magic of team spirit.
Ein lächelnder Mann mit grauem Bart und Haaren trägt ein schwarzes Poloshirt und eine graue Hose mit Händen in den Taschen.
Ein lächelnder Mann in einem schwarzen Poloshirt und Jeans steht mit verschränkten Armen.

Kai Becker

My strength lies in the targeted management of complex projects and transformations. From many years of project experience, I know how to overcome challenges and ensure sustainable results.

My Expertise

  • 10+ years of professional experience as a management consultant and project manager
  • Extensive expertise in IT transformation and project management
  • Project experience in automotive, telecommunications, banking & insurance, as well as rail transport
  • Close collaboration with project and department managers as well as top management

My Approach

My goal is to combine efficiency, quality, and sustainability in projects while deploying the right specialists at the right time. As a passionate athlete, I know how important discipline, endurance, and team spirit are for success – values that I consistently incorporate into my professional work.

FAQ

Was unterscheidet ISG von anderen Personalberatungen?
Welche Leistungen bietet ISG an?
Wie schnell kann eine Position besetzt werden?
Wie sieht der Besetzungsprozess für Unternehmen aus?
Wie diskret läuft der Research ab?
Was ist Interim Management genau?
Warum brauche ich eine/n Interim Manager:in?
Was kostet ein/e Interim Manager:in und wie erfolgt die Abrechnung?
Für welche Branchen ist ISG aktiv?
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