# Introduction

The project plan you create and refine represents your best estimate of how your project will work. It can include key information such as task start and finish dates, resource assignments, and costs. But how will you know if your project is proceeding according to plan? How will you know, for instance, if your project will finish on time or within budget? The best way to track what does and doesn’t go as planned is to set a baseline after you’ve refined the project plan and before the project begins.

A baseline is essential for tracking project progress. It contains your original scheduling, resource, and cost estimates. Once you’ve compared your baseline estimates to actual data, you can make any necessary changes to your project plan. You can monitor the progress of your project to ensure that tasks are continuing on schedule, resources are completing their work in the time allocated, and costs are not exceeding your budget. A baseline provides reference points against which you can compare project progress and know whether your project needs adjusting.

When you set a baseline, Microsoft Project saves the baseline data as part of the project file. Microsoft Project displays this data in baseline fields so that you can compare baseline data to actual data. For example, when you set a baseline, Microsoft Project copies the information from the Start and Finish fields into the Baseline Start and Baseline Finish fields. You can modify the baseline itself to accommodate changes in the project such as combining, adding, and deleting tasks.

©1996-1997 Microsoft Corporation. All rights reserved.