General PI Eligibility

What’s the difference between a PD/PI, Multiple PI, a Co-PI, a Co-Investigator, and an Application PI?

PD/PI: When an individual has full responsibility & authority for the project.

Multiple PI and Co-PI: Some sponsors use the term Co-PI or Multiple PI to indicate the role has equal responsibility and authority as the lead PI (NIH uses the term Multiple PI, and NSF uses the term Co-PI). While other sponsors use the term to represent that the individual has more authority than a co-investigator but not equal authority as the PI/PD (USDA). Some sponsors use the term to represent an alternative title for a non-lead PI on a multi-PI project. Not all sponsors use this role.

Co-investigators or Co-I: This title is used to indicate the individual makes significant contributions, but does not have overall responsibility and authority for the project. They are NOT considered PD/PIs.