PPM (Project Portfolio Management) in Oracle Fusion Cloud is designed to manage and optimize project portfolios, streamline project delivery, and reduce costs. The key roles involved in Oracle Fusion PPM include:

1. Project Manager: Responsible for planning, executing, and closing projects. They manage project schedules, costs, resources, and other project elements. The Project Manager also ensures the project meets its objectives and stays within the budget.

2. Project Team Member: Involved in the execution of the project tasks and activities. They update task status, timecards, and expense reports.

3. Project Accountant: Looks after the financial aspects of projects. They manage project budgets, forecasts, costs, billing, and revenue recognition.

4. Project Billing Specialist: Responsible for billing project customers, creating invoices, managing billing contracts, and revenue recognition.

5. Project Costing Specialist: Keeps track of all costs associated with a project, including labor, materials, and other expenses. They also ensure that costs are allocated to the correct tasks and manage cost budgeting.

6. Project Portfolio Manager: Focuses on managing a collection of projects. They evaluate and prioritize project proposals to ensure alignment with organizational goals. This role also monitors project performance against strategic objectives.

7. Project Resource Manager: In charge of assigning the right resources to the right projects based on skills, availability, and project requirements.

8. Project Executive/ Stakeholder: High-level individuals who have a vested interest in the project. They provide direction, funding, and are often involved in project decision-making processes.

9. Project Administrator: Provides administrative support for project management processes, including documentation, data entry, and report generation.

10. Grants Manager (for those organizations managing grants): Responsible for managing grant proposals, awards, budgets, and reporting.