Systems thinking is a principle that is part of the integrated process, which is a collaborative and holistic approach to green building design, construction, and operation. Systems thinking involves understanding the interrelationships and interactions among the various components of a system, such as the building, its occupants, its site, its climate, and its energy sources. Systems thinking helps to identify synergies, optimize performance, avoid unintended consequences, and create multiple benefits for the project13. Reference: LEED v4 Green Associate Candidate Handbook1, LEED v4 BD+C Reference Guide3

LEED AP credentials can contribute a point under the Innovation category, which rewards projects for achieving exceptional or innovative performance above the requirements set by the LEED rating system12. Having a LEED AP with specialty on the project team is one of the possible strategies to earn this point, as it demonstrates expertise and commitment to the green building process34. The specialty credential must match the rating system of the project4.
Reference:
Innovation | U.S. Green Building Council
LEED v4.1 BD+C | U.S. Green Building Council
Get a LEED AP with specialty on your team | LEEDuser
LEED professional credentials | U.S. Green Building Council

The U.S. Green Building Council (USGBC) administers the LEED rating systems development. The LEED rating systems are frameworks that provide guidance and criteria for designing, constructing, operating, and maintaining green buildings. The USGBC is responsible for developing, maintaining, and updating the LEED rating systems through a consensus-based process that involves various stakeholders, such as technical experts, industry leaders, government representatives, and public comments. The LEED Green Associate Candidate Handbook states that "USGBC is committed to transforming the way our buildings are designed, constructed and operated through LEED" [1, p. 7]. Reference: LEED Green Associate Candidate Handbook, [LEED Rating Systems | U.S. Green Building Council]

A closed system is a type of approach that promotes the conservation of materials and resources by linking elements in order to form relationships with their function1. A closed system is one that does not exchange matter or energy with its surroundings, and therefore minimizes waste and maximizes efficiency2. A closed system aims to achieve a circular economy, where resources are reused, recycled, or recovered, rather than disposed of3. A closed system can also enhance resource productivity, reduce environmental impacts, and foster innovation4.
Reference:
Zero Waste Definition
Closed system | physics
Material Resources, Productivity and the Environment
Sustainable Materials Management: The Road Ahead