Project Management vs Systems Engineering: Are they interchangeable?

A systems engineer will usually guide the engineering process. So while other disciplines are generally focused on design and building a product, the system engineer focuses on understanding the objectives, transferring the customer objectives into an engineering style product description, creating actionable requirements, and guiding the production of the product.

For anyone familiar with SE, you will realize this is a very high level view of responsibilities, but it is a 1000 foot wide 1 inch deep view for anyone not familiar with SE.

Project managers are expected to guide the project through each of the five phases of the lifecycle: Initiation, Planning, Executing, Monitoring, and Closing. While the PM has different responsibilities throughout each phase, generally they are controlling the project timeline to ensure it completes within the expected budget, quality, and time.

The PM will do this by managing the risks, resources, budget, and ensuring the scope (what the project is) is met but not exceeded. The PM will regularly keep the customer updated on any issues or changes arise so the customer can make critical decisions as needed.

I understand this is an extremely high level of what a systems engineer and a project manager does, but again, few PMs become SEs, and few SEs become PMs, so there is a surprising gap of information between these two disciplines. From personal experience, there is often confusion in todays corporate environment about the responsibilities of each discipline.

To me, these two disciplines are different but equally important for large or complex projects.

Overall a systems engineer will guide the engineering portion of the project, while a project manager will control the project from a high level. A system engineer will create engineering style requirements, and ensure the product will meet those requirements. A project manager will ensure that product meets the scope of the project and ensure the customer agrees that the scope matches their original objectives.