The role healthcare systems can play in surmounting global challenges like climatic change and resource scarcity is large, considering the major social and environmental impact. The research investigates the role of organizational behavior in influencing the adoption of sustainability initiatives in Greek healthcare organizations in regard to climate change. The research surveys 379 healthcare professionals from the public and private sectors with regard to organizational attitudes toward climate change, the adoption of sustainable practices, and individual environmental perspectives. Results underline that health care administration is still cut off from environmental considerations, with limited employee involvement in such initiatives of sustainability. The major barriers were poor communication, lack of education, and inadequate awareness across institutions. The study also emphasized that healthcare organizations need to align their values with environmental strategy so they can work in unison toward seeking sustainability. These would be stimulating initiatives for more leadership and active staff who become involved in making meaningful contributions toward global sustainability from the healthcare sector.