In 1995, Tetra Pak, a Swedish food packaging machine-manufacturing firm with facilities around the world, published an excellent handbook titled Project Working Model. The Tetra Pak CEO described his firm as "the project oriented company." Many project management principles found in this unusual and excellent manual echo those we have developed during years of experimentation and experience. One principle most emphasized is that project management should be a continuous learning experience. To that end, both we and Tetra Pak insist that a project manager keep a project diary.
 Leif Ögárd, Project Working Model, a guide for project managers, Effect, Effectusgruppen Malmö, Illustrations, layout, and original: TPM Information: Váxjö AB, Sweden, 1995, Tetra Pak, Lund Sweden.
In the 1940s and 1950s, a project manager carried a 3 1/2 by 5 inch loose-leaf notebook in a hip pocket for project notes. There are obviously better ways to do this today, but no matter how it is done, a project manager should keep a diary!
This diary must cover the highlights of project planning. This includes the agenda for every planning process meeting, meeting notes, and activity notes, such as the effort to create a critical path chart. The key elements of these notes should be 1) what we did, 2) why we did it, 3) what problems came up, 4) how they were solved, and 5) what we learned.
When project execution is underway, the project manager should fill a page or section of the diary for every task that is performed. During the walkabout, the five key elements should be kept in mind while communicating with workers, and appropriate records should be kept. If e-mail is used to communicate, all e-mail including the replies should be added to the notes. These notes and the information accumumlated within the project planning software package will provide source material for the project report and for the discussion of "what we learned," which is held with the team at project's end.
By keeping a diary, the project manager will be able to provide the customer with a valuable project report. A diary also will help both the project manager and the team grow in their project management skills.
The best way to keep a project diary today is to set up a file and format in a computer word processing package, and, on a daily or at least a weekly basis, bring it up to date. If using Microsoft Word® and Microsoft Project Management® software, the project manager can "paste" in project information and e-mail material to create a useful record.