Consultant, interim or do it yourself? An honest decision guide

The difference does not lie in the person but in the role and the responsibility. A consultant works from outside on a topic. She analyses, develops solutions, facilitates workshops, gives recommendations. Implementation stays with your organisation. That is as it should be, because the organisation is meant to learn, not the consultant.

An interim manager works from inside in a function. She takes on a role with responsibility, for example head of lean, head of operations or the leadership of a department, for a defined period. She makes decisions, leads people, is accountable for results. She is part of the line, not beside it.

From this follows the practical difference: a consultant leaves behind a concept and capable people. An interim manager leaves behind implemented change and, if she is good, capable people too. The consultant is in the plant when workshops take place. The interim manager is there when the line is down in the morning.

From my experience there are typical situations in which a temporary mandate fits better than consulting.

• A key role is suddenly vacant, and the ongoing programme must not come to a standstill. Recruitment takes time, interim bridges the gap.
• The organisation knows what needs to be done but has nobody to lead it. The concept exists, the implementation is missing.
• An area has to be stabilised in a short time, for example after a customer audit, a supply shortage or a change of leadership.
• A new plant, a new line or a site relocation has to be ramped up, and your own team is fully occupied with daily business.
• The management team wants to fill a role on a temporary basis first, in order to clarify how it should be shaped permanently.

What all these cases have in common: they need someone who takes responsibility and is present in everyday work. Not someone who writes an expert report.

There are equally situations in which an interim mandate would be wrong. If you do not know where your plant stands and where the lever lies, you first need diagnosis: a maturity check, a value stream analysis, an outside view. That is consulting.

If your leadership team is complete but methods and mindset are missing, you need enablement: training, coaching, support at the gemba. An interim manager who takes over the work would prevent exactly what you need. The organisation does not learn if someone else does it.

And if a topic requires neutrality, for example a conflict between departments or facilitation between the management team and the workforce, the role from outside is the right one. Anyone who is part of the line is a party to it.

So the honest question is: are you missing knowledge or are you missing a person? For knowledge: consulting. For the person: interim. Often the answer is both, in that order.

A plant with several production areas had built up a lean programme that depended on a single person. When that person left the company, there were boards, standards and a plan, but nobody to lead the whole thing. Plant management tried it themselves for a few weeks and noticed that the shopfloor meetings were dropped as soon as they were needed somewhere else.

A consultant would have been of little help in this situation. The concept was there. What was missing was someone who stands at the board in the morning, follows up on actions, works with the department heads and keeps the management team informed. A temporary mandate took on this role with a clear brief: stabilise the programme, prepare the succession, anchor the knowledge in the company.

The last point is decisive. An interim mandate that only fills gaps leaves the same gap behind when it ends. A good mandate works from the start on making itself redundant: building internal champions, documenting standards, inducting the successor.

Whether consulting or interim: the person has to fit your plant. For that I have a few questions I recommend to management teams.

Has the person worked in the line themselves, or only advised? Anyone who has carried responsibility in a plant knows what a machine breakdown on a Monday morning feels like. That shapes the way someone builds solutions.

Can the person lead without formal power? In an interim mandate you may have authority, but the team knows you will leave again. What counts is persuasion. I led laterally for years, without disciplinary authority, and consider that the best school for temporary mandates.

Does the person speak the language of both shop floor and office? Lean and change play out between the hall and the office. Anyone who knows only one side overlooks the interfaces where most of the time is lost.

And: does the person want to make themselves redundant? Ask about it. The answer tells you a lot about their attitude.

An interim mandate needs a clear framework, otherwise it becomes a permanent solution without a decision. I recommend defining four things before the start.

First, the brief: what should have been achieved by the end, and how will you recognise it. Not as a wish list, but as a few verifiable results. Second, the role: what responsibility, what authority, who is the contact in the management team. Third, the duration, with a defined end and an interim point at which both sides check whether the mandate still fits. Fourth, the handover: who takes over afterwards, when does the induction start, what knowledge must be documented.

With this framework, an interim mandate is a very effective way of bringing change into the plant. Without it, it is just an expensive stand-in. The difference lies in the preparation, and that lies with you.