Strength.
Authenticity.
Purpose.

Let’s discuss how you can build strong relationships, advance your career, and enhance your impact & influence through coaching, training and mastermind groups.

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Executive Coaching, Leadership Development & Mastermind Groups

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Executive Coaching

Onyx Leadership Collective provides transformative coaching services to help leaders navigate their personal and professional challenges, elevate their leadership presence, and become powerful forces for good.

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Targeted, Interactive Training

Our comprehensive leadership development programs equip leaders with the skills and strategies to excel in high-stakes environments, rise through organizational ranks, and influence positive change.

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Mastermind Groups

Onyx Leadership Collective helps develop and lead peer-driven Mastermind Groups, bringing together leaders from diverse backgrounds to foster community, accountability, and shared problem-solving.

Overcoming Barriers, Accelerating Career Advancement, and Increasing Impact & Influence

Onyx offers a supportive environment where leaders can make mistakes, learn, and emerge stronger. By focusing on self-awareness, embracing discomfort, and seeking accountability, leaders who partner with Onyx are equipped to overcome adversity, unlock their full potential, and inspire those around them.

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Our Mentor-Coach & Leadership Philosophy

At Onyx Leadership Collective, we believe that the journey to exceptional leadership begins with deep self-awareness. Our coaching philosophy centers on helping leaders gain clarity about who they are, what drives them, and how their unique identities influence their leadership style. We empower leaders to develop an authentic leadership presence rooted in their personal values and experiences, rather than conforming to external expectations.

The Onyx Philosophy

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Founder & CEO Marvin Chambers

Marvin Chambers, the founder and CEO of Onyx Leadership Collective, grew up in East Baltimore, a neighborhood where sports were central to life and identity. Marvin quickly became a playground legend due to his immense talent in baseball, earning respect from his peers. Yet, despite his talent, confidence didn’t always come naturally. His self-doubt would sometimes emerge during the most critical moments.

More About Marvin

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What People Are Saying

“The OLC coach empowered me with tools and resources that I still use today and I share with others that I lead. He centered me as a client and shared resources that were designed with me in mind. Additionally, he took the time to get to know me and my values. He demonstrated this when providing feedback, especially if my actions did not align with my values.”

Dirron Allen, Associate Vice President, Student Affairs

“My sessions with Marvin were far more insightful, impactful and meaningful than I ever imagined it to be. I gained a perspective into myself that was more than just helpful in my career but as a husband, father and as a man. My only regret was in not availing myself of Marvin's services sooner than I did.”

Theodore Chung, Executive Fellow

“Marvin has been my Executive Coach for over two years, and his guidance has been transformative in fostering a positive mindset and focusing on what truly matters for long-term success. He has helped me build stronger relationships with peers, tackle challenges effectively, and approach both life and work with clarity and optimism.”

Justin Denham, Chief Information Officer

“Marvin is a phenomenal coach. He quickly identifies your strengths and helps you take them to the next level. More importantly, he helps you see the blind spots, which often holds us back. Working with Marvin landed me a promotion.”

Luis Disotaur, Behavioral Health Executive

“Marvin quickly builds meaningful rapport and creates a safe space for open dialogue. His expertise in assessment tools and coaching methodologies has greatly benefited me as a leader for my family, organization, and community. As an African American man, I value Marvin’s ability to relate to my experiences, which has been invaluable in addressing challenges and fostering my growth.”

Darrell Farewell, Executive Director

“I fully credit my increased business development skillset to Marvin. He provided relevant information and was able to tailor his coaching skills to how I learn. As a partner in a national CPA firm where business development is critical to my success, I am grateful to have Marvin as a coach and mentor.”

Sean Honda, Accounting Firm Partner

"Marvin helped me reframe limiting beliefs into empowering perspectives and clarify my strengths. Through his guidance, I developed a refined vision for roles aligned with my career goals. Marvin’s support extended beyond professional insight. His coaching equipped me to approach human services work with resilience and a sustainable, healthy outlook."

Tyronne Jolly, Public Sector Healthcare Strategist

"After many years as a senior leader in the non-profit world, I was confident in my skills and impact. However, working with Marvin has transformed my leadership approach, bringing greater commitment, excitement, and clarity to my vision. From our first sessions, Marvin guided me through an in-depth examination of my beliefs, skills, and leadership style, which challenged me to grow personally and professionally."

Felix Matlock, Jr., Regional Vice President

"My coaching experience with Marvin has been transformative, both personally and professionally. Personally, it has increased my self-awareness and confidence, helping me navigate challenges with clarity and emotional resilience. Professionally, Marvin has enhanced my leadership skills, equipping me with tools to make more effective decisions, lead with purpose, and manage my team with empathy."

Tarricke Mills, Senior Director of Human Resources

“Working with Marvin was a transformative experience for my professional journey. His insightful guidance and unwavering support was instrumental in helping me achieve my career goals. Marvin possessed an exceptional ability to identify my strengths and areas for growth through his uniquely framed thought provoking questions.”

Richard Muttai, Manager of Quality Assurance

“Marvin Chambers is an incredibly gifted coach, trainer and leader. With tremendous experience and wisdom he challenges you to dig deep, to face your strengths and your weaknesses and to use them to help you become the best leader you can possibly be. His listening skills, honesty, and passion combined with his love for seeing people and organizations reach their highest capacity is truly special.”

Reggie Pickett, Pastor

"Working with Onyx Leadership Collective has been transformative for me. Coaching helped me successfully pivot into a challenging new executive role."

Alvin Saafir, Chief Credit Officer

“Marvin's coaching has helped to transform the way I think and act, which has helped me to be more successful. My personal and professional relationships have improved, and how I work has improved. I'm in a much better position—mindfully, personally, and professionally—than I was when I started this process with Marvin over a year ago. Marvin is a great coach. Hands down.”

Gabe Vasquez, Marketing Operations & Growth Strategies

“Onyx Leadership Collective has been a game changer in helping me sort out my leadership brand and how to execute it. His unique blend of business acumen, emotional intelligence, and coaching expertise has allowed me to gain clarity on my vision, prioritize effectively, and develop the leadership skills necessary to drive growth and success in my business.”

Ronald Wagner, CEO & President

"My time with Marvin was truly transformational. He provided a collaborative, supportive, and safe coaching experience that was both intentional and flexible, helping me grow in tangible ways. Marvin created a space where I, as a Black man, felt affirmed and understood—a rare and invaluable support system that allowed me to unpack my work, identify what energized and drained me, and align my career with what I truly enjoy."

Dr. Curtis Webb, Director of Systems Redesign and Community-Centered Research

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Email

info@onyxleadershipcollective.com

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Phone

301-442-7897
866-434-0825 (Toll Free)

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We focus on empowering leaders of color to unlock their full potential by cultivating both horizontal and vertical development — essential for thriving in today's complex work environments.

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Strength.Authenticity.Purpose.