Time management is a critically important skill for any successful project manager. I have observed that Project Managers who succeed in meeting their project schedule have a good chance of staying within their project budget. The most common cause of blown project budgets is lack of schedule management. Fortunately there is a lot of software on the market today to help you manage your project schedule or timeline.
Duration, resources, dependencies
Tasks, predecessors, successors
- Critical Path
Changeable, often multiple, float
Any project can be broken down into a number of tasks that have to be performed. To prepare the project schedule, the project manager has to figure out what the tasks are, how long they will take, what resources they require, and in what order they should be done. Each of these elements has a direct bearing on the schedule.
If you omit a task, the project won't be completed. If you underestimate the length of time or the amount of resources required for the task, you may miss your schedule. The schedule can also be blown if you make a mistake in the sequencing of the tasks.
Build the project schedule by listing, in order, all the tasks that need to be completed. Assign a duration to each task. Allocate the required resources. Determine predecessors (what tasks must be completed before) and successors (tasks that can't start until after) each task. It's pretty simple and straightforward. For instance, think of a project called "Getting Dressed In The Morning". The task "put on shirt" may have a longer duration if it is a buttoned dress shirt than if it's a pullover. It doesn't matter which order you complete the tasks "put on right shoe" and "put on left shoe", but it is important to complete the "put on pants" task before starting the "put on shoes" task.
The difficulty in managing a project schedule is that there are seldom enough resources and enough time to complete the tasks sequentially. Therefore, tasks have to be overlapped so several happen at the same time. Project management software (see sidebar) greatly simplifies the task of creating and managing the project schedule by handling the iterations in the schedule logic for you.
When all tasks have been listed, resourced, and sequenced, you will see that some tasks have a little flexibility in their required start and finish date. This is called float. Other tasks have no flexibility, zero float. A line through all the tasks with zero float is called the critical path. All tasks on this path, and there can be multiple, parallel paths, must be completed on time if the project is to be completed on time. The Project Manager's key time management task is to manage the critical path.
Be aware, that items can be added to or removed from the critical path as circumstances change during the execution of the project. Installation of security cameras may not be on the critical path, but if the shipment is delayed, it may become part of the critical path. Conversely, pouring the concrete foundation may be on the critical path, but if the project manager obtains an addition crew and the pour is completed early it could come off the critical path (or reduce the length of the critical path).
Regardless of how well you manage the schedule and the resources, there is one more critical element - managing the budget.