There is too much confusion when it comes to understanding the roles of product manager and project manager. They sound the same after all but are totally different job functions.

The product manager is responsible for every stage of a product like development, sales and marketing and customer support after the sale.

He or she has P&L responsibility for the product and is measured by how much income is generated by the product.

A product could have many projects working toward it competition or improvements. As such one or more project managers could report to the product manager.

The project manager is responsible for a given project. At the end of that project, the manager could move to another project related to the product or to a totally a new product.

The product manager stays with the product long after a project is done.

Below I have listed the responsibilities of each job.

Product manager

Responsible for every phase and stages of a product lifecycle

Has ownership of the product in the corporation

Helps to create the product specification and roadmap

Controls the specification for the product, the budget, and the resources

Has P&L responsibility

Directly interfaces with the customer

Holds the long-term vision of the product

Has one or more project managers working on the product

Reports to senior management or CEO

Forecasting responsibility

Has responsibility for Sales and marketing groups

Measured by the success of the product and revenue added to the company

Stays with the product when the project is completed

Project Manager

Responsible for the project

Helps to write the specification for the project

Reports to the product manager

Manages budget and resources allocated to the project

Creates and leads a team, monitors and reports their activities

Chooses the tools and the project methodology used in the project like the Waterfall Agile or Hybrid

Measured by on time and on budget delivery of the project

At the end of the project moves to another project either related to the same product or another

Conclusion

A product manager acts more like the CEO of a product, or its mother. A project manager helps to bring one or more version of the product to the world, or a midwife.

A good product manager knows the value a good project manager brings to the product and strives to hire the best.

After all, it is the project manager who is ultimately responsible to deliver the product to the market on time and on budget.

But this is the product manager who dreams about the product, natures the idea from concept to successful market introduction.

The product manager makes sure the product gets required attention by the customer, by the press, and by the senior management.