Define Activities Process in PMBOK Guide

Before we reached the process of defining activities, we created a scope management plan that guides how to define the scope. Then, we defined assumptions and constraints, the scope was defined and we created a scope statement. In the previous process, we created a work breakdown structure by dividing the scope into manageable parts and reduced the work contained in the project to the level of work packages, which is a level that cannot be further decomposed.

What is define activities process? What are the outputs of the process?

In this process, we will decide what activities we need to implement to fulfill the things determined within the scope of the project, and at the end of the process, we will get a very useful list of activities. This activity list will be very useful for us when determining the human resources needed by the project, when making cost estimates, resource estimates and duration estimates of the work packages contained in the work breakdown structure in the knowledge area of schedule management, in the knowledge area of resource management and in the knowledge area of cost management.

Another important output of the process is activity attributes. This can be an attachment to the original activity list or a separate document depending on the documenting approach of the project. Activity attributes consist of information about each project activity defined as a part of this process. This information consists of almost every necessary knowledge about an activity such as logical relationships, successor or predecessor activities, requirements of resources, predetermined completion or start dates, assumptions, and constraints.

The third main output of the process is the milestone list. Milestone lists depicts specific date goals to be reached in the project. Along with the name and date of milestones, milestone list typically involves information if a milestone is mandatory or preferential, whati is the source of the milestone, what is its importance etc. The last output of the process is change request as it is in many other process.

What are the inputs to the define activities process?

It is useful to have a scope management plan and a scope baseline when defining what project activities are. On the other hand, enterprise environmental factors and organizational process assets will be one of our inputs, as in most processes.

Which tools and techniques can be used to define project activities?

When determining what activities are, we basically use the decomposition method, just as in the process of creating the work breakdown structure. But this time, the point we start decomposing differently will be work packages, not the scope baseline.

Basically, what we need to think about is being able to determine what activities we need to do when creating this work package. another consideration we take into account when determining activities and activity attributes are the fact that projects are progressively elaborated. At this point, we will need to clarify the definitions that we will make as the characteristics of the project become clear using rolling wave planning.

Comments: 
1- Defi 08.06.2021
A project is composed of activities, so i think it is more than preparing a basis for the schedule in my opinion. Project activities are the scope itself in many ways. So a careful decomposition needs to be one in order to reach the essence of all activities and a project manager should do a thorough research to get the right activity attiributes.