Sequence Activities - PMBOK 6 Process

In PMBOK 7 the sequence activities are still an integral part of projects planned with a predictive approach. In order to develop a project schedule, the second step is defined as sequencing activities that are decomposed by using the project scope.

In the process of defining the activities, we determined the project activities by taking into account the rolling wave planning. The process of sequencing activities is the project management process in which we analyze the order in which activities should be implemented while moving forward with the goal of creating a schedule.

What is the sequence of processes in PMBOK 6?

In order to efficiently manage the time, we have to create a project schedule. Therefore we need to determine when we should conduct each activity in the project. To do so, having knowledge about the sequence of these activities is of vital significance. The process of sequencing activities consists of defining the relationship between project activities and documenting these relationships identified before, into the paper.

Some project activities include priority completion relationships. If this is a priority relationship, it can be caused by dependence between activities or efficiency considerations. Therefore there should be a sequence of activities related to internal and external dependencies, constraints, and assumptions. In this process, the activities included in the activity list which was created at the end of define activities process, are organized according to the order in which they should be implemented. 

What is the main purpose of the sequence activities process?

The main purpose of sequencing is to bring logical and feasible order of conducting activities during the execution phase by taking into consideration internal and external dependencies, assumptions, and constraints a feasible sorting with maximum efficiency is the goal. Therefore, by sequencing, it will ease the whole process of developing a schedule later. Being aware of at which step you will take the action will contribute to better planning of all activities.

Why is the sequence activities process important?

It is an important process because the essential step of developing a project schedule is to know priority completion dependencies between activities and we can only determine a definite time period by defining the sequence of them. For example, if you are carrying out a project about painting a house lining the wall should come before painting the wall. If this sequence is neglected, there would be rework or extra usage of resources and mandatory changes on the schedule.

When to perform sequence activities process?

In the process of sequencing activities, all factors are examined and the activities in the activity list are sorted and this ranking is reflected in the document. The process of sequence project activities is implemented immediately after the process of defining the activities and immediately before the process of creating a schedule. Knowing what to do when and during a project's lifecycle allows us to better plan when managing project constraints.

The sequence activities process is in the planning process group and schedule management knowledge area. The main output that we have at the end of the process is schedule network diagrams. This diagram will be of very much value while we prepare the final schedule.

The main output of the sequence activities process is project schedule network diagrams. These diagrams are graphical methods that depict the activities included in the schedule, their dependencies, and the sequence of these activities. In the schedule network diagram, the exact sequence and logical relationships between the activities are depicted. It is usually created by using scheduling software.

Inputs of sequence activities process

Activity lists: As it consists of the names of activities to be sequenced, this is the most important input of the sequencing activities process. The activities in the project's activity list are organized and shown with a diagram of the order in which they will be implemented.

Activity attributes: This document may consist of useful information which will affect the sequence of activities. Because it contains information about activities used in this process, this is also an important input as this information may change the order of activities.

Milestone list: In our project reaching the predefined milestones is one of our objectives. Therefore we have to take them into consideration while sequencing the activities. Milestones are usually determined out of control of the project by customers, stakeholders or management whereas activities are performed inside the project. Therefore, activities must be sequenced by taking milestones into consideration.

Schedule Management Plan: It is the guide for us to the necessary work of sequencing. The techniques used, the software to use, the roles and responsibilities about deciding the final logic of dependencies are included in the plan.

Assumption log: Assumptions and constraints are among the main factors to decide the dependencies and priority relationships. Assumptions are everything that we think is true about the project. The assumption log will be an input of this process because we will sequence activities according to assumptions also.

Organizational Process Assets: Project dependencies mentioned in the portfolio and program plans, existing planning procedures, templates, and lessons learned repository are useful inputs.

Enterprise Environmental Factors: Existing standards of the industry, Project management information system, scheduling softwares in the market are examples of EEF to use.

Tools and techniques used in sequence activities process

Precedence Diagramming Method (PDM): It is a form of data representation that visually reveals the logical relationships between activities and activities, the priority relationship. It was developed manually before, today most people use scheduling softwares instead. This method creates a graphical representation of activities so that the activities in the schedule can be completed. Accordingly, each activity is represented by a node. By using arrows, dependencies between activities are shown.

Dependency Determination and Integration:  Dependencies are factors that may significantly affect the ranking of activities. That's why dependencies need to be determined to sort out activities.

Three different types of dependencies exist in projects. These are mandatory dependencies which may be also mentioned as hard logic or essential in project management exams, the second is discretionary dependencies also called soft logic or preferred dependencies and the third is external dependencies which are caused by parties outside of the project. These first two dependencies may coexist with external and internal dependencies. 

For instance, in a construction work of a roof, the mainline of the roof must be built to lay tiles. If these two considerations are defined as two activities in the project, at the beginning of the activity of laying tiles depends on the end of the activity of building the main line of the roof.

Leads and Lags: Lag can be defined as the total amount of time when a successor activity is delayed after the predecessor activity. And lead is exactly the reverse of a lag. In network diagrams, it is an acceleration in a successor activity.

Project management information system (PMIS): This system is very useful in almost all scheduling processes.

See Also: 

How to Define Activities in Project Management,