Rachel McAllister is Co-Founder and Chief Executive Officer of Millennium Building Solutions (MBS), a commercial cleaning company serving corporate, institutional, and industrial clients across Pennsylvania, New Jersey, and Delaware. Since founding MBS in 2019, Rachel has led the company’s strategy, growth, and organizational culture, positioning it as a reliable, structured, and long-term partner for its clients.

With a professional background in architecture and experience leading organizations in highly regulated and high-responsibility environments, Rachel brings a systems-oriented perspective that integrates processes, people, and purpose. Her approach connects operational excellence with human values, ensuring that business decisions generate positive impact for clients, employees, and the broader community.

Under her leadership, MBS has grown strategically and sustainably by expanding operational capabilities, strengthening its organizational structure, and increasing its regional presence. This growth included the integration of another industry company (Dillon Building Services) and investment in long-term infrastructure through the acquisition of an office in Jeffersonville — reflecting a commitment to stability, scalability, and responsible expansion.

Rachel is a Certified Chaplain and has provided emotional and spiritual support in sensitive settings such as hospitals, fire and police departments, and among vulnerable populations. This work has strengthened her empathetic leadership, ethical framework, and ability to manage complex human dynamics within professional environments.

She has also been actively involved in humanitarian and community initiatives focused on education, family support, and social development, both locally and internationally. This commitment to social responsibility is central to her identity as a leader and is reflected in the culture she fosters within MBS.

Prior to MBS, Rachel owned and led a pharmaceutical company, gaining experience in regulatory compliance, risk management, and operations within critical industries. This background informs her disciplined, transparent, and structured approach to business leadership.

Rachel-McAllister

Rachel is married and values family, community, and service as core pillars of a balanced life and purpose-driven leadership. This perspective shapes the way she builds relationships, leads teams, and makes responsible, long-term business decisions.

Rachel is known for her high standards, integrity, and ability to build relationships based on trust, value, and long-term vision. Her mission is to lead organizations that combine operational excellence with meaningful social impact, creating sustainable value for clients, employees, and communities.