Manager of Project Managers: A senior position, in larger organizations they might be referred to as VP of project management, responsible for overall direction and management of projects.
The title of "Sr." in any professional capacity should be given based on knowledge and years of experience, as opposed to leadership function.
The word “lead” in a job title typically indicates a low-level supervisory position similar to an assistant manager or management trainee. The word “senior,” however, may be given to mid- or upper-level managers handling larger duties within an organization.
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