Project Scheduling And Resource Leveling

We all know that in the real world we, as PMs, are2) As soon as possible (flexible; default) - For
given the finish date of the project before we evenprojects scheduled from the start date. Schedules
have a chance to plan for it. This is a good enoughthe earliest possible start and finish dates for the
reason why we need to get better at scheduling ourtask
projects and leveling our finite resources.3) Finish no earlier than (moderate; avoid) - For
Sure, there are tools that allow us to automate theprojects scheduled from the start date. Indicates the
process but a tool is as good as the knowledge ofearliest possible date that the task can be completed,
those who use it. All in all, all PMs have a tool and aand the task cannot finish any time before the
method by which we create our project schedules.specified date
But... we all suffer from common mistakes such as4) Finish no later than (moderate; avoid) - For
having the wrong dependencies, excessiveprojects scheduled from the finish date. Indicates the
constraints, inadequate level of detail in the WBS,latest possible date that the task can be completed,
estimates too granular or inexistent, over allocatedand the task can be finished on or before the
resources, etc. Ring a bell?specified date
The tool that is most widely used is MS Project®5) Start no earlier than (moderate; avoid) - For
(MSP). And I am not going to take the time of thisprojects scheduled from the start date. Indicates the
article to talk about MSP since this is not the topic. Iearliest possible date that the task can begin, and the
will, however, mention it as it applies to projecttask cannot start any time before the specified date
scheduling and resource leveling.6) Start no later than (moderate; avoid) - For
The method is what changes from PM to PM. I willprojects scheduled from the finish date. Indicates the
explain the "must do" steps and in the correct order.olatest possible date that the task can begin, and the
Develop WBStask can start on or before the specified date
Most organizations have a hierarchical structure to7) Must finish on (inflexible; avoid) - Indicates the
break down the work. Typically, it looks like this:exact date on which the task must finish. Other
Stage, Phase, Task/Deliverable/Milestone.scheduling parameters such as task dependencies,
This is a way to organize and define the total scopelead or lag time, and resource leveling become
of the project by decomposing the work to besecondary to this requirement
executed into tasks that the project team can8) Must start on (inflexible; avoid) - Indicates the
execute and create the required deliverables. Theexact date on which the task must begin. Other
tasks, deliverables or milestones are components thatscheduling parameters such as task dependencies,
can be scheduled, cost estimated, monitored andlead or lag time, and resource leveling become
controlledo Establish dependenciessecondary to this requiremento Assign resources
Dependencies are defined so that the work isResources (typically human) are assigned to tasks,
executed in the proper order. Understand thedeliverables and milestones that need to be
following task dependency types before you useexecuted. At the beginning of the project, when
them; incorrect dependencies will impact the finishnamed resources are not known yet, roles are
date of your schedule and create unnecessaryassigned that can later be replaced with names (i.e.:
constraints:the role of Analyst is assigned to a task during
1) Mandatory (hard logic) - Inherent in the nature ofproject scheduling and is later replaced with John Doe
the work being done. They often involve physicalwhen he is the analyst assigned to the task)o Level
limitations (i.e.: a test case must be defined beforeresources
testing)Helps in utilizing resources consistently throughout the
2) Discretionary (soft/preferred/preferential logic) -project. Ensures resources are not over allocated.
Based on experience, desire or preferences (i.e.: theHelps the PM avoid delays caused by bad allocations.
team decides that they will create the user manualHelps the PM identify and take advantage of unused
after the first round of testing, although it is nottimes by analyzing task dependencies. MSP can
necessary)automatically level resources based on resource
3) External - Based on needs or desires of a partycalendar, task types, dependencies, and constraints,
outside the project (i.e.: the server must behowever, I have yet to find a PM that has felt
purchased before configuring)comfortable with the way MSP does it. I level
A network diagram is used to show dependencies inresources manually via the Resource Usage view, but
a graphical form. MSP generates a network diagramif you insist in using the automatic feature of MSP,
automaticallyo Estimate worksave a copy first.
Work is the number of labor units (usually expressedIf you find resource conflicts (over or under
in hours, days or weeks) required to complete aallocations) you could:
scheduled task. Estimation is equivalent to success.1) Delay certain tasks
Duration is the total number of work periods (usually2) Assign a different resource
expressed as days or weeks) required to complete a3) Change task dependencies
scheduled task.4) Remove tasks
When estimating, keep in mind the different task5) Add tasks (instead of using the MSP's split task
types:functionality which is not supported by some project
1) Fixed units (MSP default) - Allows the schedule tomanagement systems (i.e.: Clarity)o Determine critical
calculate the finish date ASAP based on resourcepath
availabilityHelps the PM identify tasks that must be carefully
2) Fixed duration - Used when the priority is tomonitored. The critical path is the longest duration
preserve duration. To complete work, assignpath through a network diagram and it is the
resources as needed to satisfy the finish dateshortest path to complete the project. Knowing the
(remember my comment about "knowing" the finishproject's critical path should be the goal of the
date before we even plan?)scheduling process. MSP calculates the critical path
3) Fixed work - Some project management systemsautomatically and through the Gantt chart it shows
(i.e.: Clarity, formerly Niku) that sit on top of MSPwhat tasks are in it. One thing to keep in mind is that
don't support this type because of the effort drivenas tasks are completed ahead or behind schedule the
nature of it and the unpredictable results it maycritical path changes. Another is that there can be
create. So, I have chosen to get used to not to usemore than one critical path but this increases risk.
it at allIf the critical path takes your project's finish date
This is how task types work:way too far there are a couple of techniques that
...if you revise Duration ...if you revise Work ...if youPMs can use to compress the schedule:
revise Units1) Fast tracking - Perform critical path tasks in parallel
In a Fixed Units task... Work is recalculated, and unitsthat were originally planned sequentially. It usually
are fixed Duration is recalculated, and units are fixedincreases risk and often results in rework
Duration is recalculated, and work is fixed2) Crashing - Assign additional resources to critical
In a Fixed Duration task... Work is recalculated, andpath tasks while maintaining scope. Almost always
duration is fixed Units is recalculated, and duration isresults in increased costs
fixed Work is recalculated, and units are fixedAs PMs, we forget a very important intangible:
Task constraint is the next item we need to look atresource calendars affect project scheduling. Public
when estimating. You must avoid using moderate andholidays or time off in a resource's calendar makes
inflexible types. Wrong constraints increase thethose days as non-workdays and therefore, MSP
project risk and extend the finish date:skips them altogether.
1) As late as possible (flexible; default) - For projectsIf you follow the basic steps explained in this article
scheduled from the finish date. Schedules the latestyou should not have major problems with scheduling
possible start and finish dates for the taskand resource leveling. Don't you think so...? Well, I do.