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Executive Transition Consultant

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Consultant Details:

Contact: Melissa Tillman
Name of Firm: Nonprofit Growth Advisors
Language Spoken: English, Spanish
Website/LinkedIn URL: www.nonprofitgrowthadvisors.com

Consultant Expertise

Organizational assessments, Board development, Recruitment, Executive coaching, Transition consulting & project management, DEI, Communications strategy

Program Areas

Arts and Culture, Community and Economic Development, Education, Environment, Health, Human Rights, Human Services, International Relationship, Philanthropy, Public Affairs, Public Safety, Social Sciences

Legal Structure of Organization:

LLC

Year Practice Founded:

2021

Number of Individuals in Firm:

12

Names and Titles of Individuals in Firm:

Melissa Tillman, MBA
Founder & CEO
Rhea K. Mac, MPP
Senior Nonprofit Growth Advisor
Whelma Cabanawan, MBA
Senior Nonprofit Growth Advisor
Maggie Weisberg, MBA
Senior Nonprofit Growth Advisor
Janice Oyama
Nonprofit Growth Advisor

Names and Titles of Individuals in Firm:

Melissa Tillman, MBA
Founder & CEO
Rhea K. Mac, MPP
Senior Nonprofit Growth Advisor
Whelma Cabanawan, MBA
Senior Nonprofit Growth Advisor
Maggie Weisberg, MBA
Senior Nonprofit Growth Advisor
Janice Oyama
Nonprofit Growth Advisor

Firm or Consultant Address:

Los Angeles, CA 90019

RFQ Contact Name:

Melissa Tillman

RFQ Contact Phone:

310-622-3171

Geographic area currently served by firm (select all that apply):

Los Angeles, California, USA, International

How would you describe the range of diversity reflected in your firm’s consultants and leadership (or self, if sole practitioner)?

NGA is a women-owned leadership advisory firm with a multidisciplinary team that reflects diverse professional backgrounds, lived experiences, languages, and areas of expertise. Our advisors include seasoned nonprofit executives, interim leaders, governance specialists, facilitators, fundraisers, and organizational development professionals with experience serving organizations and communities across Southern California and nationally. Collectively, NGA’s advisors speak English, Spanish, Hindi, Punjabi, Thai, Filipino, and Ukrainian, enabling us to better serve organizations and communities with diverse cultural and linguistic backgrounds. We believe diverse perspectives strengthen governance, improve decision-making, and help organizations build more inclusive and sustainable futures.

Please describe your mission, values, and approach:

NGA helps mission-driven organizations navigate periods of growth, transition, transformation, and organizational change. NGA partners with boards and executive teams to evaluate strategic opportunities, strengthen governance, facilitate collaborative decision-making, and build resilient organizations positioned for long-term impact.

NGA believes every organization is unique. Rather than applying a one-size-fits-all consulting model, NGA tailors every engagement to the organization’s mission, culture, capacity, relationships, and strategic goals. Clients benefit from the collective experience of seasoned nonprofit executives and advisors who bring expertise across executive leadership, governance, organizational development, fundraising, human resources, communications, behavioral health, strategic planning, and organizational transformation.

Drawing upon proven frameworks, practical tools, shared resources, and trusted relationships cultivated across the nonprofit sector, NGA helps boards and executive teams evaluate opportunities, navigate complexity, build alignment, and implement thoughtful solutions. Whether facilitating strategic partnership exploration, supporting governance alignment, serving in an interim or fractional executive capacity, or guiding implementation, NGA works alongside organizations to strengthen leadership, build organizational capacity, and position collaborations for long-term success.

What expertise or perspective do you bring to organizations looking to ground their collaboration practices in values of diversity, equity, and inclusion?

NGA believes successful collaborations are built on trust, transparency, mutual respect, and meaningful stakeholder engagement. Every organization brings its own history, culture, strengths, challenges, and relationship to the communities it serves. NGA tailors each engagement to honor those differences while creating opportunities for shared understanding and alignment.
NGA designs collaborative processes that encourage diverse perspectives, elevate the voices of those closest to the work, and foster inclusive decision-making among boards, executive leaders, staff, and other key stakeholders. NGA’s multidisciplinary advisory team brings diverse professional backgrounds, lived experiences, and language capabilities, enabling NGA to support organizations with varying cultures, missions, governance structures, and community relationships.
Rather than applying a standardized approach or assuming a predetermined outcome, NGA helps organizations build the trust, communication, leadership alignment, and decision-making structures necessary to evaluate strategic opportunities, establish equitable partnerships, and advance positive outcomes for the communities they serve.

Please describe your ideal engagement. Feel free to include issue area and scope of project:

NGA’s ideal engagements typically span 3 to 18 months, depending on the organization’s goals, complexity, and stage of growth or transition. NGA partners with boards and executive leadership teams during periods of executive transition, organizational transformation, governance modernization, strategic planning, strategic partnership exploration, and long-term sustainability planning. NGA also provides interim and fractional executive leadership, executive coaching, governance advising, facilitation, organizational assessments, and implementation leadership and support to help organizations navigate change with confidence.

NGA serves nonprofit organizations of varying sizes and mission areas, including behavioral health, homelessness, child welfare, family services, youth development, education, arts and culture, legal advocacy, financial empowerment, philanthropy, and membership associations. NGA has experience supporting both 501(c)(3) charitable organizations and 501(c)(6) membership associations.

NGA remains engaged beyond strategy development to facilitate implementation, build leadership capacity, strengthen governance, and help organizations achieve lasting organizational change.

How many executive-transition related projects have you or your firm been involved with?

12+

Please describe your fee structure:

NGA utilizes a flexible fee structure tailored to the scope, complexity, duration, and stage of each engagement. Services may be structured as project-based engagements, monthly retainers, interim or fractional executive leadership, facilitation, implementation support, or hourly consulting, depending on the organization’s needs. NGA works collaboratively with participating organizations to develop a clear scope of work and investment that reflects the level of facilitation, leadership, assessment, planning, and implementation support required.

What percentage of your clients are within the nonprofit sector?

100% NGA exclusively serves nonprofit organizations and mission-driven associations, including 501(c)(3) charitable organizations and 501(c)(6) membership associations. NGA’s clients range from community-based organizations to regional, statewide, national, and international nonprofits navigating executive transitions, governance modernization, organizational transformation, fundraising, strategic partnerships, and long-term sustainability.

Are you open to remote engagements?

Yes

Briefly name and describe 1-3 examples of executive transitions with which you have been involved as a consultant (please prioritize NSI-funded and/or LA-based organizations).

Masada Community Mental Health Services (Los Angeles County, CA)
NGA is currently serving as Interim Chief Executive Officer, providing executive leadership during a period of organizational transformation and CEO transition. NGA’s scope includes organizational stabilization, executive leadership alignment, governance support, financial and operational strategy, board partnership, fundraising leadership, and strategic partnership exploration. NGA continues to guide the organization through an executive transition while positioning it for long-term sustainability.

Food on Foot (Los Angeles, CA)
NGA served as Interim Executive Director during a nine-month executive transition and partnered closely with the Board of Directors to stabilize the organization, strengthen operations, lead an office relocation, expand community partnerships, and support the successful onboarding of the organization’s current Executive Director. NGA remained engaged throughout the transition to help ensure leadership continuity and long-term organizational stability.

AADAP, Inc. (Los Angeles, CA)
NGA served as Interim Chief Executive Officer during a period of executive transition and organizational growth. Working closely with the Board of Directors and leadership team, NGA provided organizational stabilization, executive leadership, operational oversight, governance support, and strategic guidance while leading organizational growth, including the opening of a new service location. Following the transition, NGA supported the onboarding and executive coaching of the incoming Chief Executive Officer and continues to partner with the organization on strategic initiatives and executive leadership support.

Add any other information you feel would aid in understanding the value you or your consulting firm can bring to an organization preparing for or implementing an executive transition:

NGA believes executive transitions present a unique opportunity to strengthen governance, align leadership, build organizational capacity, and position nonprofits for long-term success – not simply replace an executive. This philosophy guides every engagement and shapes NGA’s approach to helping organizations navigate change with confidence while building stronger, more resilient organizations for the future.
NGA provides a continuum of support that may include organizational assessments, facilitation, governance advising, interim and fractional executive leadership, executive coaching, onboarding support, implementation, and long-term advisory services. This integrated approach enables NGA to meet organizations where they are and provide the level of support needed throughout every stage of the transition process.
NGA’s multidisciplinary advisory team brings firsthand nonprofit executive leadership experience across a wide range of mission areas and organizational structures, including both 501(c)(3) charitable organizations and 501(c)(6) membership associations. The team includes former Chief Executive Officers, Executive Directors, and senior nonprofit leaders with advanced graduate education in nonprofit management and public policy, BoardSource governance expertise, Certified Interim Executive leadership, and specialized experience in governance, organizational development, facilitation, and organizational transformation. By combining practical executive leadership experience with proven frameworks and thoughtful implementation, NGA helps boards and executive teams navigate change with confidence while building stronger, more resilient organizations prepared for their next chapter.

Please list up to 5 Consultants from your firm

Melissa Tillman
me*****@*********************rs.com
https://www.linkedin.com/in/melissajtillman/
Melissa Tillman is the Founder & CEO of Nonprofit Growth Advisors, a certified women-owned consulting firm helping nonprofits thrive through interim and sabbatical leadership, fundraising strategy, and board development. With more than 20 years of nonprofit leadership experience, she has guided organizations through complex transitions, raised millions in charitable dollars, and built sustainable systems for growth. Melissa holds an MBA in Nonprofit Management and is certified in nonprofit governance and interim executive leadership.

Rhea K. Mac, MPP – Senior Nonprofit Growth Advisor
rh**@*********************rs.com
https://www.linkedin.com/in/rheakmac/
Rhea K. Mac offers expert nonprofit consulting services designed to drive systemic change and enhance organizational effectiveness. With a strong commitment to social equity, she specializes in providing strategic support across various domains, ensuring nonprofits achieve their mission and maximize their impact. Rhea’s specialties include nonprofit development, fundraising, interim executive leadership, organizational strategy, strategic planning, corporate board management, and capacity building. Rhea is a member of various leadership councils, boards, and LA-based local government committees and is most notably involved with the Empowerment Congress. Additionally, Rhea is passionate about social equity-driven photography. Each chapter of Rhea’s life story includes championing change towards creating a more equitable space for all Angelenos – especially for the youth and future generations from whom current generations are borrowing land, space, and time.

Whelma Cabanawan, MBA – Senior Nonprofit Growth Advisor
wh****@*********************rs.com
https://www.linkedin.com/in/whelmafc/
Whelma Cabanawan brings nearly two decades of leadership experience in the nonprofit sector, specializing in operational management, financial oversight, and talent development. With an MBA in Nonprofit Management and a PhD in Organizational Leadership (ABD), she has guided organizations through significant growth and transitions. Whelma’s expertise spans people and culture, risk management, grant writing, and fundraising, making her a versatile asset. Certified in DEI and professional coaching, Whelma is committed to fostering inclusive environments and empowering teams. Her holistic approach combines operational excellence with a deep understanding of movement-building, making her an invaluable consultant for any nonprofit seeking transformative impact.

Maggie Weisberg, MBA – Senior Nonprofit Growth Advisor
ma****@*********************rs.com
https://www.linkedin.com/in/maggie-weisberg-mba/
Maggie Weisberg has spent over 20 years in the nonprofit sector—working with everyone from the boiler room to the board room, from grassroots to the elite, from an all-volunteer team to managing large teams and hundreds of volunteers at one time. Growing up, she could never put a finger on exactly what she wanted to be: a doctor, a teacher, the president, a cat or a librarian. No matter the career path, or the decision-making ability of a five-year old, she always knew her calling was community-focused. Maggie is a solutions-based nonprofit leader and advisor with a unique and varied blend of hard/soft skills translatable to all sectors. She has a genuine interest and proven track record for helping people and programs reach their full potential. Maggie thrives in an environment with many moving parts and loves putting together puzzle pieces to create the best results possible.

Janice Oyama – Nonprofit Growth Advisor
ja****@*********************rs.com
https://www.linkedin.com/in/janice-oyama-880240194/
Janice has worked in the nonprofit and social services field for 15+ years, where she supported vulnerable populations through direct services, program development, and organizational advancement. Her expertise is centered in equity and inclusion initiatives, change management, and employee engagement. Janice is trained in trauma-informed care and as an intergroup dialogue facilitator, so she understands the value of creating meaningful connections and building partnerships to benefit those we serve. Her passion for positive impact and disrupting the status quo continues to fuel her motivation in developing herself and others. Janice’s focus remains on fighting for social equity and values working with others to elevate nonprofits that share a similar vision to advocate for positive change in overlooked communities.

Do you always conduct an organizational assessment as a part of your scope of work?

NGA considers organizational assessments a core component of its approach because they provide valuable insight into an organization’s culture, governance, leadership capacity, operational effectiveness, and readiness for change. While every engagement is tailored to the client’s unique needs, NGA strongly recommends an organizational assessment whenever appropriate to inform decision-making, build stakeholder alignment, and develop practical recommendations that strengthen long-term organizational sustainability.

How (or do) you involve senior staff and other stakeholders in the process

Yes. NGA believes successful executive transitions are built on trust, transparency, and meaningful stakeholder engagement. Depending on the scope of the engagement, NGA conducts confidential interviews, surveys, facilitated discussions, leadership team meetings, board workshops, and listening sessions with senior staff and other key stakeholders. NGA’s approach is tailored to each organization and designed to ensure diverse perspectives inform the transition process while maintaining appropriate confidentiality throughout the engagement.

Prior to narrowing the pool of candidates for a client, do you make it a practice to share the full list of applicants with the client?

NGA is not an executive search firm. When partnering alongside a retained search firm, NGA supports boards through executive transition planning, governance, organizational readiness, interview planning, executive onboarding, and implementation. Candidate recruitment and review processes are established collaboratively between the Board and the retained executive search firm.

Do you identify/place interim executives?

Yes. NGA provides experienced Interim Chief Executive Officers and Executive Directors during planned and unplanned leadership transitions. NGA also assists organizations in identifying qualified interim and fractional executive leaders through its trusted professional network when additional expertise or capacity is needed. NGA’s goal is to provide stable leadership, organizational continuity, and thoughtful guidance while boards prepare for and onboard their next permanent executive.

Do you have a minimum fee?

NGA’s engagement fees are customized based on the scope, complexity, and duration of each project. NGA works collaboratively with clients to develop an approach that aligns with their organizational needs, priorities, and budget.

What percentage of your searches are for LA-based organizations?

While NGA does not conduct executive searches, the majority of NGA’s executive transition, interim leadership, governance, and organizational advisory engagements have been with Los Angeles County-based nonprofit organizations. NGA also serves nonprofit organizations throughout California and nationally.

What is your track record of placing BIPOC candidates?

While NGA does not serve as an executive search firm, NGA is committed to supporting equitable and inclusive leadership transitions. NGA partners with boards to design thoughtful transition processes that encourage broad and diverse candidate pools and align with each organization’s mission, values, and leadership needs. NGA’s experience includes supporting organizations led by and serving historically underrepresented communities, and NGA’s multidisciplinary advisory team reflects diverse professional backgrounds and lived experiences.

Do you have a guarantee policy or an “off-limits” policy?

Because NGA does not provide executive search services, traditional search guarantees and off-limits policies do not apply. NGA maintains the highest standards of confidentiality, professionalism, and ethical practice in every engagement and avoids conflicts of interest that could compromise clients or the integrity of the executive transition process.