Welcome to SistahBoss

The premier leadership development resource for Black women in the Pacific Northwest. Offering professional development and mentoring/coaching customized to the unique experiences of Black women leaders.

SistahBoss was launched in March 2023 by mother and daughter duo, Mary Wideman-Williams and Marquinta Obomanu. The vision for SistahBoss is to equip & encourage Black women leaders through their career journeys. SistahBoss clients develop effective leadership skills and practices through workshops, events & individual coaching. This work is rooted in a commitment to support & inspire Black women and girls to be leaders across all sectors and at all levels. SistahBoss is more than a company – it’s a movement!

Mary Wideman-Williams

Co-Founder

Mary Wideman-Williams, MPA believes leadership is more than a title. It's how we show up for ourselves and those we influence. As Co-Founder of SistahBoss, she is dedicated to equipping Black women with the tools, confidence, and perspectives they need to lead with purpose and create lasting impact.

Drawing on decades of private/public sector executive leadership experience and organizational development expertise, Mary designs transformational learning programs and coaches both emerging and established leaders. She is passionate about customizing leadership development curriculum centered around the unique needs of Black women in leadership roles.

In addition to her work with SistahBoss, Mary serves as an Affiliate Associate Professor at the University of Washington's Evans School of Public Policy & Governance, where she teaches in the Executive Master of Public Administration (EMPA) program. She is a leadership strategist, speaker, consultant, and coach. Her greatest joy is being a resource and supporter for leaders at all levels so they can thrive in career, family, and community.

Boss Moves Headshots_ Last Forever Images00064 (1).jpg

Marquinta Obomanu

Co-Founder

Marquinta Obomanu, MPA knows that connection and community are key to the growth and development of Black women leaders. As Co-Founder of SistahBoss, she is passionate about creating spaces where Black women can develop practical leadership skills, build supportive networks, and be inspired to grow both personally and professionally.

Marquinta leads the design of the SistahBoss skill-building programs and signature events, creating engaging opportunities for Black women to strengthen their leadership capacity and expand their professional toolkit. She is intentional in her focus on helping to cultivate leadership competencies, especially among young professionals. Her background in the non-profit and education sectors shapes and informs her commitment to this work.

Whether facilitating a workshop, leading a cohort, or hosting a community gathering, Marquinta specializes in encouraging SistahBoss clients in their leadership journeys.