In the context of project management, a key driver is a factor that has a significant impact on the success of a project. It is a critical element or constraint that must be carefully managed and monitored to ensure that the project remains on track and achieves its objectives.

Key drivers can vary depending on the nature and scope of the project, but common examples include:

1. Time: The project's schedule and deadline are key drivers, as delays or missed milestones can have a significant impact on project success.
   
   
2. Cost: The project budget and financial constraints are important drivers, as overspending or unexpected expenses can jeopardize the project's viability.
   
   
3. Scope: The project scope defines the objectives and deliverables of the project, and ensuring that they are met is a key driver of success.
   
   
4. Quality: Meeting quality standards and ensuring that deliverables meet customer expectations is a key driver, as failure to do so can impact the project's reputation and future business opportunities.
   
   
5. Stakeholder expectations: Managing stakeholder expectations and ensuring that their needs are met is a critical driver, as failure to do so can lead to dissatisfaction and project failure.
   

Identifying and managing key drivers is essential for successful project management, as it helps to prioritize resources, mitigate risks, and ensure that the project stays on track to achieve its objectives.