Mackenzie Health Executive and Leadership Team

October, 2026

Leadership Overview

Mackenzie Health has 8 executives leading key functions including clinical strategy, financial oversight, medical planning, and public affairs.

Committed to delivering exceptional patient care across Ontario, Mackenzie Health advances medical innovation through specialized cancer care, mental health services, and pediatric excellence to improve community health outcomes.

Leadership Roles at Mackenzie Health

  • President & Chief Executive Officer - Nicole McCahon
  • President & Chief Executive Officer - Carmine Stumpo
  • Interim President & Chief Executive Officer - Mary-Agnes Wilson
  • Vice President, Finance & Chief Financial Officer - Gregory Chow
  • President & Association Volunteer - Zina Villamagna
  • Chief Technology Officer - Patrick Harkins
  • Vice President, Medical Planning & Chief of Staff - Stephen Jackson
  • Vice President, Public Affairs & Chief Communications Officer, Stakeholder Relations - Allison Trenholm
  • Nicole McCahon - President & Chief Executive Officer

    Nicole McCahon, the President & Chief Executive Officer at Mackenzie Health, directs the overarching clinical strategy and operational excellence of the organization. McCahon manages the integration of specialized cancer care and pediatric services to ensure high-quality patient outcomes across the Ontario region. By aligning departmental goals with the broader mission of community health, the President & Chief Executive Officer fosters a culture of continuous improvement and medical innovation. This leadership role involves constant collaboration with the Board to secure long-term sustainability and resource allocation for critical healthcare infrastructure. Through rigorous oversight of hospital operations, Nicole McCahon drives the expansion of mental health programs to meet growing regional demands. Ultimately, the President & Chief Executive Officer maintains the highest standards of safety and efficiency within the healthcare network, ensuring that every patient receives comprehensive and compassionate medical support.

    Carmine Stumpo - President & Chief Executive Officer

    Carmine Stumpo, the President & Chief Executive Officer at Mackenzie Health, architects the strategic vision for large-scale hospital operations and facility management. Stumpo focuses on optimizing ICU capacity and emergency response protocols to enhance the resilience of the healthcare system throughout Ontario. By streamlining administrative workflows, the President & Chief Executive Officer improves the delivery of specialized medical services and patient throughput. This role requires deep engagement with external stakeholders and government partners to secure funding for advanced medical technologies. Carmine Stumpo drives the implementation of digital health solutions that modernize patient care pathways and improve clinical accuracy. Through the coordination of multidisciplinary teams, the President & Chief Executive Officer ensures that the organization remains at the forefront of hospital-based care, consistently meeting the complex needs of the diverse population served by the network.
    Carmine Stumpo

    Mary-Agnes Wilson - Interim President & Chief Executive Officer

    Mary-Agnes Wilson, the Interim President & Chief Executive Officer at Mackenzie Health, stabilizes organizational performance while guiding the transition of key clinical and administrative initiatives. Wilson oversees the continuity of essential services, including cancer care and mental health programs, ensuring that patient care remains uninterrupted during periods of leadership evolution. By facilitating clear communication between the executive team and medical staff, the Interim President & Chief Executive Officer maintains operational cohesion across all hospital departments. This role involves evaluating current service models to identify opportunities for increased efficiency and improved patient satisfaction. Mary-Agnes Wilson drives the execution of short-term strategic goals that support the long-term viability of the healthcare provider. Through diligent monitoring of performance metrics, the Interim President & Chief Executive Officer secures the stability of the organization, allowing the medical teams to focus entirely on delivering high-quality care to the Ontario community.

    Gregory Chow - Vice President, Finance & Chief Financial Officer

    Gregory Chow, the Vice President, Finance & Chief Financial Officer at Mackenzie Health, manages the fiscal health and long-term financial planning of the organization. Chow oversees the allocation of capital for medical equipment, facility upgrades, and operational expenses to ensure the sustainability of cancer care and other critical services. By analyzing financial performance data, the Vice President, Finance & Chief Financial Officer identifies opportunities for cost optimization and revenue growth. This role involves working closely with the Board to provide transparent reporting and strategic financial guidance. Gregory Chow drives the development of budgets that support the expansion of healthcare services while maintaining fiscal responsibility. Through the management of financial risk and resource distribution, the Vice President, Finance & Chief Financial Officer ensures that the hospital network possesses the necessary capital to deliver exceptional care to the community while navigating the complex economic landscape of the healthcare industry.

    Zina Villamagna - President & Association Volunteer

    Zina Villamagna, the President & Association Volunteer at Mackenzie Health, leads the coordination of volunteer services and community-based support programs. Villamagna oversees the integration of volunteer efforts into the daily operations of the hospital, enhancing the patient experience through compassionate support and administrative assistance. By fostering a culture of service, the President & Association Volunteer strengthens the connection between the hospital and the local community. This role involves recruiting and training volunteers to assist in various departments, including patient navigation and family support services. Zina Villamagna drives the development of programs that leverage volunteer talent to improve the overall quality of care and patient comfort. Through the management of these essential community resources, the President & Association Volunteer ensures that the organization benefits from a dedicated network of supporters, ultimately contributing to a more holistic and patient-centered approach to healthcare delivery in Ontario.

    Patrick Harkins - Chief Technology Officer

    Patrick Harkins, the Chief Technology Officer at Mackenzie Health, directs the digital transformation of the hospital network by implementing advanced health information systems. Harkins manages the secure integration of electronic medical records and diagnostic data to support clinical decision-making across all departments. By architecting scalable cloud infrastructure, the Chief Technology Officer ensures that medical teams have reliable access to critical patient information during emergency procedures. This role involves collaborating with the C-suite to align technological investments with the broader mission of improving patient outcomes. Patrick Harkins drives the adoption of cybersecurity protocols that protect sensitive health data while maintaining seamless connectivity for staff and patients. Through the deployment of innovative software solutions, the Chief Technology Officer enhances the efficiency of hospital operations, ultimately supporting the delivery of high-quality care throughout the Ontario region and beyond.
    Patrick Harkins

    Stephen Jackson - Vice President, Medical Planning & Chief of Staff

    Stephen Jackson, the Vice President, Medical Planning & Chief of Staff at Mackenzie Health, coordinates the strategic alignment of medical staff and clinical resources. Jackson oversees the planning of new medical programs, ensuring that specialized services like Pediatrics and ICU care meet rigorous quality standards. By facilitating communication between the medical staff and the executive leadership, the Vice President, Medical Planning & Chief of Staff ensures that clinical priorities remain central to the organizational strategy. This role involves managing physician recruitment and retention to maintain a high-performing medical workforce. Stephen Jackson drives the development of evidence-based care protocols that improve patient safety and clinical outcomes across the network. Through the oversight of medical planning, the Vice President, Medical Planning & Chief of Staff ensures that the hospital remains prepared to address the evolving healthcare needs of the Ontario population with precision and expertise.

    Allison Trenholm - Vice President, Public Affairs & Chief Communications Officer, Stakeholder Relations

    Allison Trenholm, the Vice President, Public Affairs & Chief Communications Officer, Stakeholder Relations at Mackenzie Health, directs the organization's reputation management and community engagement strategies. Trenholm oversees the communication of clinical achievements and public health initiatives to ensure transparency and trust with the Ontario community. By managing relationships with government officials, donors, and community partners, the Vice President, Public Affairs & Chief Communications Officer, Stakeholder Relations builds the support necessary for hospital growth. This role involves crafting messaging that highlights the impact of specialized services like mental health and pediatric care. Allison Trenholm drives the execution of public awareness campaigns that educate the public on available medical resources. Through the coordination of stakeholder relations, the Vice President, Public Affairs & Chief Communications Officer, Stakeholder Relations ensures that the organization maintains a strong, positive presence, effectively advocating for the needs of patients and the healthcare system.
    Allison Trenholm

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    Frequently Asked Questions Regarding Mackenzie Health Top Executives and Leadership Team

    Who leads Mackenzie Health?
    Mackenzie Health is led by Nicole McCahon (President & Chief Executive Officer), along with executives such as Carmine Stumpo (President & Chief Executive Officer) and Mary-Agnes Wilson (Interim President & Chief Executive Officer).
    Who is part of Mackenzie Health’s executive team?
    The executive team of Mackenzie Health includes leaders such as Nicole McCahon (President & Chief Executive Officer), Carmine Stumpo (President & Chief Executive Officer), Mary-Agnes Wilson (Interim President & Chief Executive Officer) and other senior executives.
    How many executives does Mackenzie Health have?
    Mackenzie Health has 8 executives leading key business areas.
    What roles are included in Mackenzie Health’s leadership team?
    The leadership team of Mackenzie Health includes roles such as President & Chief Executive Officer, President & Chief Executive Officer, Interim President & Chief Executive Officer, Vice President, Finance & Chief Financial Officer, President & Association Volunteer.