b4035917_roject__Program__and_Portfolio__Portfolio
[Characteristic] Change [Project] Project manager expects change and implements processes to manage and control it. [Program] Program manager must expect changes from both inside and outside the program and thrive on them if they help maximize the strategic benefits and objectives of the program. [Portfolio] 
Portfolio manager continually monitors changes in the broader context of the strategic plan of the organization.
Become a Certified Project Manager: Chapter 13: Relationship between Project, Program, and Portfolio
Portfolio