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Listed below are some suggestions on what not to do when preparing a schedule. Please note there are exceptions to most rules, so the following are guidelines to use, especially if you are an inexperienced scheduler. 1. Avoid too much detail. One frequent mistake is creating too many tasks, which can make the schedule unmanageable. Avoid this mistake by using a high-level project schedule based on the project deliverables. More detailed sub-schedules can be prepared for each phase or for major deliverables and linked to the project schedule. 2. Don’t Link Summary Tasks. A summary task is a group of related tasks aggregated at a summary level. Linking two summary tasks with a finish-to-start relationship means that all of the predecessor tasks must be completed before any of the successor tasks can be started. However, many times you can start some of successor tasks before the entire preceding summary task is completed. The rule is to only link the lowest level tasks, and do not link summary tasks to other tasks or summary tasks. 3. Watch for hangers. A basic scheduling rule is that every task in the schedule should have at least one predecessor and at least one successor, except for summary tasks. When a task lacks a predecessor and/or successor, the task has a hanger, which is an unintended break in the schedule logic. The problem is that the forward and backward pass, which calculates the earliest and latest start and finish dates, will be incomplete and possibly wrong because each hanger results in a dead end. For more on the forward and backward pass, see the April 25 feature. 4. Don’t enter start or finish dates. If you input a start date, you add a “start no earlier than” constraint to the task. If you input a finish date, you add a “finish no earlier than” constraint to the task. In both cases you are forcing dates, and defeat the value of having the schedule software determine dates based on schedule logic and durations. Let your scheduling software calculate the task's start and finish dates! 5. Avoid Constraints. Constraints impact schedule dates. Assume you add a “must finish on” constraint of 4 August for Task A, and that the calculated completion date for Task A, before you added the constraint, was 11 August. The scheduling software will follow your constraint command and show the 4 August completion, which results in five days of negative slack. This is equivalent to adding a new task with a minus-five-days duration just before Task A. This is impossible, so you might as well label the new task “Miracle Occurs.” The point is, avoid using constraints and be aware of how constraints impact your schedule! There is one final recommendation that will help improve your schedule. The Gantt view is not really useful for checking the schedule since it’s difficult to follow task relationships. The network diagram view is also not very useful since you need to scroll up and down, left and right to see the entire network diagram. A good practice is to plot the entire schedule (many copy companies can print this for you) and hang it on a wall. When this is done the project team inevitably finds mistakes in the task relationships and opportunities to improve the schedule. Mr. Lukas is vice president of PMCentersUSA. He leads a team of instructors and consultants in delivering project management and business analysis training and consulting to clients across the country. He has been involved in project management for more than 30 years and his experience spans information systems, product development, capital construction and manufacturing projects. PMI Launches New Scheduling Credential
This week, PMI launched the PMI Scheduling Professional (PMI-SP)SM credential at the fifth annual PMI College of Scheduling Conference in Chicago, Illinois, USA. The College was instrumental in helping PMI to develop this credential. PMI President and CEO Gregory Balestrero was the keynote speaker and presented on the importance of scheduling. Vice President of Product Management Brian Weiss announced the details of the new credential and its importance to practitioners. PMI exhibited and had staff available to answer questions about the PMI-SP credential, assist schedulers through the application process and answer general PMI questions. The PMI-SP acknowledges individuals who strengthen and support project teams by providing expertise in the specialized area of scheduling. Find out more on the PMI-SP eligibility requirements, examination and credential fees.
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What Not to Do When Preparing a Project Schedule 
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