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Optimal Project Team Size
By Vesa H Autio

This article is about planning the size and composition of business development project teams. It is a boring one. Don’t read any further as it does not have a clear advice but just some batting.

The simple approach to build a development project team is to nominate a project manager and an adequate amount of resources to do the planned development tasks. If it is this simple why do development projects run over costs and timetable. Not having an optimal project team may be one reason. Some considerations about this issue are presented here.

An imaginary business development project has been calculated to require 1600 man days of development work. One full time developer is estimated to be able to work 20 days per month. If the project should be done in 10 months, then eight full time developers would be required to do the job. Most probably one project manager would be nominated to run this project.

One project manager, eight developers and ten months. Would the project succeed?

To answer this project manager’s time management could be studied. Project manager’s time is divided between different tasks. At a minimum, if the company is very efficient, 10% goes for general matters outside the project. After this a project manager, like the team members, has about 20 days per month for actual project management.

About 15% of the project manager’s time goes for managing project’s stakeholders. This covers steering group meetings and different kind of communication with the project’s stakeholders. If more time is needed the project has problems (or it might be that stakeholders just love having meetings). It may be for example that the objectives are not clear or all stakeholders do not accept those. The project owner should take a strong role in this case, and even freeze the project if needed. If less time is used, then stakeholders are not respected and informed enough which leads to problems during the project, or at least in the implementation phase.

As 10% goes for general matters and 15% for managing stakeholders, 75% of the project manager’s time remains for managing the actual project team. Each project worker who is directly guided by the project manager requires 15% of her or his time. This goes for planning what they should do, communicating with them and monitoring their progress. This means that one project manager can manage five persons. If there are more developers the project manager does not have enough time to manage them properly. This causes project drifting, rework and lower quality.

With 5 developers the imaginary project would take 16 months. As the project manager needs to work full time project management would take 320 man days. In total the project would then take 1920 man days.

Let’s say we want to make the project in 12 months, but know that a team of 7 is too much for one project manager. A sub project manager should to be nominated, assuming that a suitable person able to both manage and develop is available in the team. The project manager will now manage 5 persons. One of them is a sub project manager who will, in addition to her or his development tasks, manage two other persons. Each of them requires 15% of her or his time, so the sub project manager can use 70% for development work. With a team of seven, from which one works 70% and sub-manages 30%, the 1600 man day project would take 12 months. The project manager uses 240 days and the sub project manager 72 man days for project management. This is 72 hours more than needed when 15% for project management is seen as the average. The cost would be about the same as in a 16 month project, but project closes four months earlier. The challenge would be to find the suitable sub project manager.

What about the earlier mentioned 10 month project. In theory eight workers would be enough, but one project manager cannot manage them. Again one person has to be nominated as a sub project manager with three persons to manage. But as sub project manager’s own time for actual project work decreases an additional development resource would needed. In addition to the project manager, there would be a sub project manager with some development tasks and eight full time developers. This is a bit more than needed, so the project could take a bit less than 10 months. Again, finding a suitable sub project manager may be a challenge.

What about a 5 month project then. In theory 16 workers would be enough to do the actual development work. This would require one main project manager and three sub project managers. Also the participation of stakeholders needs to be more intense. For example subject matter experts providing initial data for development need to use twice the share of their time for the project leaving less for their daily work. For a limited time, but anyway. If the project is shortened enough they should be fully committed to the project. Finding enough resources from the line organization may be an additional challenge in addition to finding suitable sub project managers.

In theory we could nominate 1600 developers and 320 project managers and get the project done in one day. If this project team needs to wait for information or decisions for one day the project costs and timetable would double. Huge teams and super fast projects should be started only if the project is super clear and can ensure super fast information logistics.

We can also nominate one developer and a part time project manager and get the project done in 1600 work days. If this project team needs to wait for information or decisions for a day, the project costs and timetable would not change much. But it would be a slow project. Somewhere between these is the optimal project team size and composition. It is dependent on the business need, and the amount and competence of the available project management, sub project management, line organization and development resources.

The absolute truth

The 15 percent used here in many places is not the absolute truth suitable for all. The actual value is dependent on the competence and maturity of the organization and its individuals, project management practices, project managers, as well as the nature of the project. The absolute truth is that there needs to be a suitable balance between project management resources and the project team composition in order to succeed in a business development project.

Vesa H Autio is a solution manager in an international manufacturing corporation and a senior adviser for a consulting company Arito-tsm. He has over thirteen years of experience in managing international IT, R&D, change and business development projects and programs. You can read more from Vesa on his blog. He can be contacted by email at

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