OneOC's expert team of nonprofit professionals provides service solutions that connect businesses and nonprofits to ultimately strengthen the communities they serve.

Click below to view staff bios.
Amanda Green– Organizational Development Services Director

Amanda Green
Organizational Development Services Director
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Amanda Green began her OneOC career in January 2019 as the organization’s first Nonprofit Solutions Strategist, managing OneOC’s in-house consulting services for nonprofit organizations. Within six months, she was promoted to Organizational Development Services Director, overseeing OneOC’s membership and training services, in addition to the consulting program.

Amanda brings experience in both the for-profit and nonprofit sectors to her role, working as a Marketing Manager for a startup SaaS company for two years, and volunteering as a Program Manager for Youth Leadership America, a leadership nonprofit organization for high school students, for five years. Amanda is an Accredited Coach from the Certified Coaches Alliance, a graduate of the Riordan Leadership Institute, and a StartingBloc Social Innovation Fellow. She holds an MBA from Chapman University and a BA in Psychology from CSU Long Beach. Amanda began her professional career at Blue Garnet, a strategy and management consulting firm for social change organizations, and credits this experience to positioning her for success in the Southern California nonprofit sector.

Bryan Myung - Training Coordinator

Bryan Myung
Training Coordinator
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Bryan joined OneOC in 2015 as the Training Coordinator where he oversees the day to day operations of the Training Program which provides Organizational and Professional Development to Nonprofit staff members in Orange County. Through this role, he implemented new software to add E-Learning into the OneOC Training Curriculum and expand the potential reach of the training courses. Bryan entered the nonprofit sector through AmeriCorps where he developed and supervised a college readiness mentoring program for teens.

Christina Hall - Volunteer Services Concierge Manager

Christina Hall
Volunteer Services Concierge Manager
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Cindy Braun – Office & Database Administrator

Cindy Braun
Office and Database Administrator
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Cindy Braun manages the development and implementation of OneOC Salesforce database and manages onsite support for all other technology related needs for the office.

Cindy has an extensive experience working in the nonprofit sector, serving through various roles within community-based nonprofits where she provides direction and support in the areas of grant management, project management, volunteer recruitment and management, special event planning and community outreach.

Prior to joining OneOC in 2010, Cindy was the Marketing Manager for two bicoastal state-of-the-art multiple million dollar data solution centers at Ingram Micro and a Project Manager at Agile360.

She holds a BS degree in Finance from California Polytechnic State University, San Luis Obispo. Cindy is a native Northern Californian and has resided in Tustin since 2003.

Deborah Pierson – Volunteer Services RSVP Manager
Deborah Pierson
Volunteer Services RSVP Manager
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Deborah D. Pierson is OneOC’s first ever RSVP Manager (Retired Senior Volunteer Program). As part of the Volunteer Infrastructure team, Deborah works with the 55+ community utilizing their passions, skills, interests and giving-back hearts to provide volunteer hours at designated nonprofit organization stations. Deborah brings over 25 years of health care services management experience in both the for-profit and nonprofit sectors, women groups, social change organizations, press/media, philanthropic charities, senior advocacy and boards such as; National Aging in Place, OC Senior Roundtable, National Association for Female Executives, Women’s Speakers Bureau, Senior Care Awards, International Toastmasters, Dale Carnegie, Miss CA/Miss America (all Volunteer-Scholarship) nonprofit Org., Saddleback Coordinated Care Council, Women of Distinction Humanitarian, Chambers of Commerce Ambassador, and Civic Community Association of Laguna Woods Village.

She holds dual BS degrees from California State University, Fresno in Health Sciences & Behavioral Health Sciences with a Minor in Women in Business Studies. She is thrilled that her RSVP role will “Re-ignite not Retire” the 55+ multi-generation by promoting an active lifestyle, health and wellness while strengthening nonprofit organization success and social impact within the communities of both Orange & San Bernardino County areas through the power of volunteerism.

Floridel Martinez- Marketing and Communications Specialist
Floridel Martinez
Marketing and Communications Specialist
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Floridel joined OneOC in 2015. She possesses a firm foundation and understanding of design and marketing principles. With almost a decade of experience volunteering, collaborating, and working with various nonprofits throughout the Los Angeles and Orange County areas, Floridel has developed a strong passion for cultivating the greater good of the community at large.

Gianna DeSanto - Administrative Specialist
Gianna DeSanto
Administrative Specialist
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Gianna DeSanto joined the OneOC team in July, 2019 and brings six plus years of administrative specialty and human services experience to the team. She holds a strong passion for nonprofit growth and enjoys the opportunity to be of service. Gianna currently lives in Eastside Costa Mesa and attends Orange Coast College.

Jaime Lizarraga – Nonprofit Accounting Specialist

Jaime Lizarraga
Nonprofit Accounting Specialist
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Jaime joined the OneOC team in June, 2019 and brings more than a decade of knowledge and experience in the fields of bookkeeping, accounting & finance. Prior to joining the OneOC team, Jaime’s work history included positions with Abbott Vascular as an On-Site Coordinator, Monster Beverage Company as a Master-Database Technician and Eastern Municipal Water District of Southern California, working directly with various Finance and Accounting departments. He has also helped launch several small business-entrepreneurs ideas and concepts into tangible, manageable, and efficient business models. Small businesses such as JB Trucking, Lucie’s Locadas, and Suzie’s Fashions. Jaime’s continued passion for helping small and large businesses thrive and succeed, not only helps create more jobs for his community, but also has a positive economic impact with other small-associated businesses and products as well.

Jaime area of expertise also include financial planning, financial budgeting, financial forecasting and business management.

Jaime earned a Bachelor’s Degree in Advanced Finance & Accounting from the University of Phoenix and is currently enrolled in a Master’s Degree program, with a concentration in Business Administration at the University of Phoenix as well.

He currently lives in Riverside County with his fiancé and their four children.

Juliana Silva – Bookkeeper
Juliana Silva
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Juliana has been with OneOC since June 2015. She has a passion for learning and sharing her knowledge to help businesses in the community. Her experience began as a Brazilian Certified Public Accountant (CPA), where she explored her talents in international accounting and finance. Juliana has an extensive knowledge of Outsourcing, Real Estate, Investment, Mergers & Acquisition, and Due Diligence. She earned a Master’s degree of Business Administration, with an emphasis in international accounting standards (IAS), and in 2013 moved to the U.S. to continue her education and development of English as a second language. Additionally, Juliana has joined a second MBA program at Southern States University in Newport Beach.

Kelley Shannon-Poisson – Nonprofit Solutions Specialist
Kelley Shannon-Poisson
Nonprofit Solutions Specialist
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Kelley Shannon-Poisson joined OneOC in 2019, following a year of grant writing for nonprofit organizations and ten years of volunteering at Bowers Museum. Kelley brings years of experience working in account management and customer relations on the for-profit side of business, and is now so pleased to be combining her business and volunteer experiences to assist Orange County nonprofits achieve their success.

Kimberly Harnish - Volunteer Services AmeriCorps Manager

Kimberly Harnish
Volunteer Services AmeriCorps Manager
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Kimberly joined the OneOC team in 2017 with over 17 years of nonprofit experience. Through her various roles, Kimberly has provided leadership in the areas of youth development, program operations, volunteer management, partnership building and family engagement.

Kimberly holds a B.S. in Child and Adolescent Development from California State University, Fullerton. She is a graduate of Leadership Tomorrow Orange County whose mission is to cultivate, inspire, connect and empower an effective community of leaders. Kimberly places great value in helping to develop individuals and encouraging others to become involved in the community. As Volunteer Services Manager, Kimberly oversees OneOC’s AmeriCorps VIP program to support the capacity building, fundraising and training/development efforts of nonprofits throughout Orange County.

Kimberly is most proud of the relationships she has built with the families, staff and community members that she has worked with. In her free time, she enjoys spending time with her two sons and their dog.

Kristin Schlick - Volunteer Services Events Manager

Kristin Schlick
Volunteer Services Events Manager
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Kristin Schlick is OneOC’s Volunteer Services Event Manager. As part of the Organizational Volunteer Infrastructure Team, Kristin works with corporate clients to plan and execute employee volunteer “Days of Service,” matching these organization with nonprofits in the hopes of facilitating lasting and mutually beneficial partnerships. Kristin brings experience from the nonprofit sectors, working as a Project Services Manager for The ALS Association Orange County and as the Marketing and Events Director at HomeAid Orange County.  She holds an B.A. from Cal State University Long Beach. Kristin began her career at Live Nation, Verizon Wireless Amphitheater, as their Summer Concert Director and is excited to use her skills and passion to strengthen nonprofits in Orange County.

Lauren Petersen – Foundation & Donor Relations Manager
Lauren Petersen
Foundation & Donor Relations Manager
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At OneOC, Lauren is responsible for developing stewardship, cultivation and recognition strategies that build relationships between charitable foundations and OneOC. Prior to joining the OneOC team, Lauren gained broad-ranging experience in frontline fundraising, event coordination, volunteer coordination, direct mail marketing, donor relations, and grant writing through her work with both national and community-based nonprofits. Energetic and reliable, Lauren loves creating ideas with wings that advance the philanthropic community.

LaVal Brewer – Director of Business Development & Partnerships
LaVal Brewer
Director of Business Development & Partnerships
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LaVal Brewer brings to OneOC more than three decades of experience in nonprofit management, with more than a decade of experience in executive and development roles. He recently supported the work of Southern California nonprofit and for-profit corporate employee volunteer programs as a consultant through the Long Beach Nonprofit Partnership and OneOC.

LaVal has served as executive director for Playworks Southern California and several YMCAs throughout Southern California. He is passionate about youth development, strengthening communities, volunteerism, and engaging for-profit organizations to address local issues. LaVal believes that employee engagement is essential at all levels of nonprofit and community development. LaVal is a trainer for CaliforniaVolunteers, serves on the board of California Communications Access Foundation, and regularly volunteers in his community. LaVal is married and has three daughters. 

Marisela Rodriguez – Bookkeeper
Marisela Rodriguez
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Marisela (‘Mari’) is somewhat of a ‘Jane-of-all-Trades’ with experience as a bookkeeper, business director, office manager, Realtor, tax preparer, mom’s caregiver, and, just for fun, a music director of a children’s/youth choir, wedding coordinator, stage director, pianist, Media Manager for On The Rocks Radio Show, and volunteer.  Her favorite role in life is 'Mom to Alexander' who keeps her laughing through thick and thin.

Mari has worked in the nonprofit arena for many years including positions at Stop-Gap Drama Therapy, the YMCA of Orange County, Venture Strategies, Our Lady of Fatima, and the Mission San Juan Capistrano. Her passions include anything Snoopy, musical theatre, her dog Wiggles, the Golden Girls (who she relates to more and more each day) and hanging out with celebrities. Mari is happy to be a new member of the OneOC Team!

Randa Wren – Nonprofit Accounting Manager
Randa Wren
Nonprofit Accounting Manager
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Randa Wren has been the Bookkeeper for OneOC since December 2012.  She has over 30 years of bookkeeping experience in construction, manufacturing and publishing.  

Rossana Healy – HR Specialist
Rossana Healy
HR Specialist
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Rossana joined the OneOC team in 2018. She has many years of nonprofit experience both as a volunteer and consultant for various nonprofits in the Orange County area. Rossana received a degree in Marketing from FIDM and a Teaching certification from UCLA. She also attended the Fashion Institute of Technology (FIT) in New York, where she received a B.A. in Advertising.

Sheila Teevans – Corporate Relations Manager

Sheila Teevans
Corporate Relations Manager
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As OneOC’s Corporate Relations Manager, Sheila strives to increase the number of Orange County companies who are actively engaged in responding to our community’s most pressing and urgent needs. Before joining OneOC in 2015, she had more than 10 years of experience in the for-profit sector, including positions at TCW in Los Angeles and Yamaha Motor Corporation in Orange County.  Sheila holds a Bachelor’s degree in Sociology and a Master’s degree in Business, both from Loyola Marymount University.  She is happy blending her business background with her own passion for community service. Sheila is a native Southern Californian; she currently lives in Anaheim Hills with her husband Duane and their two children.

Stacy Brooks – Director of HR & Administration

Stacy Brooks
Director of HR & Administration
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Stacy Brooks has over 26 years of experience as a nonprofit leader and over ten years of experience in human resources.  Prior to joining the OneOC team in 2011, Stacy’s work history included the positions of Program Manager and HR Director for Olive Crest and HR Generalist with Boys Town California.  Labeled as being “HR with heart”, Stacy is dedicated to not only ensuring that organizations remain in compliance with laws and regulations, but that they are also “doing right” by their employees.

Stacy studied Journalism and Communications at the University of Southern California and is currently working towards obtaining her Senior Professional in Human Resources (SPHR) certification.  She was recently featured in the Orange County Register where she gave advice on how to land a job using specialty job boards.

Tiffany Trevillison - Accounting Specialist
Tiffany Trevillison
Accounting Specialist
[email protected]
Tim Strauch – President/CEO

Tim Strauch
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Tim is the President & Chief Executive Officer for OneOC in Orange County, California. He has provided strategic leadership and direction with his business management acumen to help strengthen over 950 organizations in the community.  He also serves as a coach, consultant and trainer to professional leaders as well as a presenter and facilitator in the community. Tim currently serves on the California Volunteers Commission as well as on various national committees and task forces with Points of Light. Tim played an instrumental role at a state and national level with the Service Enterprise program serving over 150 organizations since its inception and has been replicated throughout the country.   

Before his current position, Tim served in various leadership roles with the YMCA including Executive Director of the Saddleback Valley YMCA, Senior Vice President of Branch Operations, Executive Vice President of Business Development and Chief Development Officer.

With over 30 years as a successful nonprofit leader dedicated to strengthening communities, Tim has guided and empowered individuals to seek their greatest potential while making a positive difference in others. His personal mission is to maximize the human potential for greater community impact.

His areas of expertise include leadership development, operations, business growth, board development, volunteer advancement, fundraising and strategic planning.    

He earned a Masters Degree in Athletic Administration from Florida State University and completed his undergraduate work at the University of Southern California.

Tim lives in Dana Point with his wife, Kristen, who is an Executive Director with the American Cancer Society. They are a blended family with kids, Max, Maddie, Nicole and Gavin.

Tracy DeMattos - Bookkeeper

Tracy DeMattos
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Tracy joined OneOC in March of 2018.  With over 15 years working in the nonprofit industry, as well as over 10 years of bookkeeping experience, Tracy believes in the value of helping others and expanding both her and her clients’ knowledge to better their businesses. She has had the opportunity to work in several industries: medical, construction, senior living and small business. In 2011, she earned her BS in Management with an emphasis in Marketing from the University of Maryland. Tracy is currently working on her MBA from Azusa Pacific University. 

A California native, Tracy finds it a blessing to be home after living on the East Coast for more than 20 years. Her passion is in helping women and teen girls thrive and overcoming obstacles that stop them from being successful. If she’s not in the office or at home, you’ll find her with family and friends or relaxing at the beach and simply taking it all in.  

Ursula Walsh – Director of Volunteer Services
Ursula Walsh
Director of Volunteer Services
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Ursula has served as OneOC’s Director of Volunteer Services for the last six years.  During that time, she has led the development and implementation of OneOC’s corporate employee engagement programs, including national Days of Service, Team Building Service Projects, Board Connection, Skills-Based Volunteering with clients including Altria, Disneyland Resorts, Fluidmaster, Hilton Worldwide, Home Depot, Hyundai Capital, Outerwall and many more.  

Ursula has over twenty years of nonprofit professional experience. Prior to OneOC, Ursula held various management positions within the YMCA, including the Executive Director of the Highland Branch.  She has served in a multitude of facilitative, board and capacity building roles for nonprofits, including a trainer & consultant for the CA Service Enterprise Initiative (CVSEI) and has received the Fred Hoshiyama Leadership and William A. Dunlap Fellowship Awards, respectively. 

She holds a Bachelor of Science degree in Human Services from Springfield College and is a graduate of the Executive Development Institute, a Y collaborative through Cornell University.  Additionally, she provides leadership for OneOC’s volunteer department, including AmeriCorps both State and National, Disaster Services, Family Service Team and the Retired Senior Volunteer Program (RSVP 55+).

Although her commitment to service is inexhaustible, her true success is through her family—Martin, her husband and her son Blaine.  They currently reside in San Clemente, CA, are avid aquatic nuts (swimming, surfing, SCUBA, kayaking etc.) and love every minute of it.

Valerie Fryer – Director of Finance & Business Services

Valerie Fryer
Director of Finance & Business Services
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As the Director of Finance & Business Services, Valerie Fryer has been handling the Financial, Human Resource and Business Services at OneOC since July 2007.

Valerie has over 25 years of experience as a financial analyst, internal auditor, sales and business planning manager and financial director, working for companies such as Taco Bell Corp., Pioneer Electronics and Disneyland Resort.

Valerie grew up doing volunteer work, and wanted to make a positive impact on people’s lives and in the community. She joined the nonprofit management industry in 2002, working for Olive Crest Treatment Centers prior to joining the team at OneOC. She holds a BA in Business Economics from the University of California, Santa Barbara, and an MBA in Business Management from Pepperdine University.

Xitlaly Luna – Volunteer Services Coordinator

Xitlaly Luna
Volunteer Services Coordinator
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Xitlaly has years of experience volunteering in educational settings in Orange County and Merced. To pursue becoming a Marriage and Family Therapist, Xitlaly graduated and received her BA in Psychology from the University of California, Merced. After graduating, she wanted to learn more about the nonprofit sector which led her to serve two years in AmeriCorps. Xitlaly hopes to bring awareness to nonprofits resources provided in Orange County and gain as much experience before going to graduate school. She hopes to motivate others to do good for our community while expanding her knowledge on working with new populations.