The way the pastry chef puts the cherry on the cake, the same way the project manager looks forward to having the results of the project accepted. This final act of the performance has two parts: the formal and the informal one.
From a bridge to an IT module, the acceptance of the project results shall be formalised in a way or another.
Some projects – in particular the development management project – require a final report. The final report requires usually to take a result-oriented perspective and show that the resources and inputs lead (or not) to the change expected and if not, why.
In other projects – mostly, internal projects – an acceptance form suffices to acknowledge that the product and/or service are in place and are accepted by the customer for use. There are a variety of acceptance forms in projects guidance and methodologies. Feel free to download and use this template: Template_ Acceptance_EN
From my experience, the formalities of completing a project are a sort of “Give to God what’s God’s and to Caeser’s what’ his”. Who is your Ceaser’s will give the answer to the question on whether or not a less formal completion of the project is needed.
From my experience, it is worth to take time to celebrate the project completion with the client and the project team. It can take a variety of shapes and forms, depending on your objective and budget. Yet, by no means a celebration of the end of the project needs to be a dull event with speeches and handshakes. For example, to mark the end of a project, at the final steering committee meeting I chose story telling. It was before Christmas, so a Christmas story with gifts – project deliverables – which were “put” under the client’s tree was very well received and remembered for years after.
What I also learned is that you need to approach the celebration of the end with the best of your project management skills. You owe it to your team first of all. They deserve to have their work acknowledged. It is also important to keep up their enthusiasm for new challenges and projects. I remember a project team which received chocolate medals at the end of a first project with the joy of kids getting treats. It was the least I could do, but it made it a memorable thing for them.