Meet Our Staff & Board


Impact Bay Area staff are Certified Impact Self-Defense Instructors, who have each completed over 150 training hours in full-force self-defense techniques. Our instructors are versed in physical, verbal and sexual abuse/assault awareness and prevention. We are committed to ending violence by sharing Impact's empowerment and self-defense classes with as many people as possible.

Our full-force courses are team-taught by a "Whistle" Instructor and a "Suited" Instructor. They work together to provide a comprehensive experience for our students.

The Whistle Instructor demonstrates physical and verbal techniques, facilitates group discussions, models how to fight back against a mock assailant, and coaches students during their fights.

The Suited Instructor wears protective gear and plays the role of an assailant, allowing our students to practice techniques from verbal boundary-setting to full-force blows in realistic scenarios.

Click here to LEARN MORE about becoming a Certified Impact Instructor.

Admin Staff


 Linda HeadshotLinda Leu, Executive Director

Linda comes to IMPACT with fifteen years of non-profit work in the Bay Area, a Master’s Degree in Public Health, and extensive experience working with policy, advocacy and fundraising. Recently, Linda served as California Policy and Research Director for a national non-profit, which allowed her to develop her management and leadership skills. She also has many years of experience working directly helping individuals recover from trauma, teaching trauma-informed mindfulness and yoga to youth and adults in the juvenile justice system and other institutions. At IMPACT, she's excited to be able to combine her love for non-profit leadership, helping people empower themselves, and addressing trauma. Linda is also super excited to be a newly certified IMPACT instructor!


maggie_pic_web.jpg Maggie Horton-Brande, Program Manager

Maggie grew up in Portland, OR and celebrates her 10th California-versary this year. She is thrilled to be on the IMPACT team after taking her Women's Basics training in 2013. As a Somatic Experiencing Practitioner, she also sees adults clients in San Francisco for chronic stress and the healing of symptoms associated with trauma. Supporting others in the sustainable experience of aliveness, ease and empowerment is her aim. She is in Buddhist ministerial training and teaches both Buddhist and secular meditation. 



Whistle Instructors 


Nicole DeVito

A cowgirl, skier, dancer, and lover of coconut frosted cupcakes, Nicole is delighted to be part of the Impact team as a certified whistle instructor.  In her own life, she relishes in the experiences of overcoming obstacles, doing things that she thought were impossible, and gently pushing herself out of her comfort zone. 

Nicole is continuously inspired by the powerful and courageous Impact students who do these very things each and every class. Outside of her work as an Impact instructor, Nicole is a licensed mind-body oriented psychotherapist with a private practice in the East Bay, an avid horseback rider, person to one cool kitty named Snoop Dogg, and a huge fan of having fun. 


Dawn Hofmeister 

Dawn took her first IMPACT class in 1991 and went on to become an assistant. She assisted with the LA chapter for many years before moving up to the Bay Area. Dawn began assisting classes in the Bay Area in 2013 and has been an instructor since 2013.

Outside of IMPACT, she is the mother of two humans and two fur babies and loves empowering teens and kids.



Rachel Marcuse

Rachel took her first Impact Class in 2013. She was blown away, not just by the practical physical and verbal skills she learned, but by the sense of community and safety the instructors and courageous students provided. Rachel started volunteering immediately and eventually became a certified whistle instructor. Rachel also serves as the staff liaison to our Board of Directors - a role we are so grateful to have her play.

Rachel loves being able to bring her 15+ years of facilitation and group process together with her background in teaching dance and yoga. In her day job, she runs People Operations (HR plus!) for an organization focused on climate change and, in her free time, she enjoys eating weird/tasty food with her husband in San Francisco.



Kathy Turner

Kathy has worked in the field of women's health for over 30 years. She took her first Impact class in 1998 and immediately experienced profound changes in her personal and professional life.

Kathy became an Impact instructor in 2000 and is dedicated to supporting women and girls in experiencing their strength, the power of their voice and their right to say No! 



 dv_headshot-edit.pngDani Villalobos

Dani is a martial artist who took her first Impact class in 2010. The Women's Basics program impressed her with its use of simple, full-force techniques and real-world scenarios, and she wanted to pass on this trauma-informed programming to others. Dani became a volunteer with the organization right away and later was certified as a Whistle Instructor.
Dani has also served on the Board of Directors for Impact Bay Area, and as Program Director. When she's not on the mat, she enjoys distance running, zombie movies, and pursuing an advanced degree in clinical psychology.



 Jenny Williams

Jenny is a martial artist who took her first Impact class in 2001. She was impressed at the sense of empowerment and the healing that she gained from that class. It offered so much more than any other self-defense class or seminar she had experienced. This class had such a positive influence on how she lived her day to day life that decided to become an assistant.

Jenny became a certified Impact Bay Area instructor in 2008. With every class she teaches, Jenny feels honored to witness the courage and power that each student brings onto the mat.  



Amanda Wagner 

Amanda took her first Impact class in 2011. The experience was so empowering she immediately signed up to become an assistant and is now a certified whistle instructor and also served as Program Director for Impact Bay Area. She has a passion for working with teens and young adults and sees great value in empowering them.

Amanda is grateful to be part of the self-defense and healing work that Impact does and continues to be inspired by the courage and strength that the students bring to every class. 




Heather took her first Impact class in September of 2008. She had such an empowering and transformative experience that she became an instructor assistant a few months later. She served as the Coordinator of Assistants for three years, helping to ensure that all of our classes had volunteer assistants to support our instructors and our students.

Heather has logged more hours volunteering for Impact than any other individual, and we're deeply grateful. She was certified as an instructor in 2012. 


 Suited Instructors



Tim Kinney

Tim has studied a variety of martial arts for over twenty years, earning three black belts and numerous full-contact fighting awards. He has been working with Impact since 2007 and has previously served on Impact's Board of Directors.

Tim became involved with Impact after seeing a friend's public celebration. His passion for teaching is sustained by the courage, commitment, and spirit he sees displayed in Impact classes. He enjoys teaching Impact classes because they are practical and healing, and is sustained by the courage, passion, and commitment that Impact students demonstrate in class.When Tim isn't running around in a big padded suit, he and his wife are walking their three dogs.



Dan Waters

Dan earned a Bachelor's Degree in Electrical and Electronics Engineering from the California State University at Sacramento in 2006. He has been an engineer for a California utility since 2006. In 2010 he became a licensed Professional Engineer.

He began his training to be a suited IMPACT instructor soon after attending his Aunt's Basics class public celebration/graduation and witnessing the power, courage, transformation and healing of each person in the class. He completed his instructor certification in December 2008. Dan lives in the Monterey Bay area with his partner Naomi, two black cats (Metaphor and Magenta), and a chocolate Lab (Sandy).



Rudy Trejo

Rudy teaches at Impact because he has a 20 year old daughter and nieces of similar ages. He feels women and men of all ages have the right to be safe! He holds a second degree black belt and is certified in Executive Protection through the International training commission.

He is a Tactical Master Instructor in the CDT Non- Deadly Force Training Commission. He currently works in corporate security. Rudy enjoys spending his free time in the great outdoors, if he’s not fishing or gold prospecting you can find him on the firing line at the range.



Robert Oryall

Robert has spent 30 years practicing various forms of martial arts. He taught hundreds of Self Defense courses to law enforcement, military personnel, bodyguards, as well as civilian men, women and children. 

He has instructed martial arts in the Bay Area since 1985, but it wasn’t until he witnessed his first Bay Area Impact class that he said, “this is how self-defense should be taught; scenario based, full impact, and with guidance to students throughout the process in real time.”  He took his first Bay Area Impact class in January 2011 with the intention to become a suited instructor.  

Robert Graduated from Notre Dame de Namur University and majored in Clinical Counseling and Administration of Non-Profits. After spending 20-years working in the Information Technology industry, Robert went to work for an LA based Private Protection firm where he doubles as a Defensive Tactics instructor for body guards. He is married with two children whom he mentors in horseback-riding, martial arts and soccer.   He enjoys traveling, camping, hiking, and golfing.  He is studying Japanese as a hobby and one of his goals this year is to compete in his first Triathlon. 



Mariko Sturgess

Mariko got her start with IMPACT in 2014 when her best friend convinced her to take a women's basics class. Since then, she's been hooked. She was blown away at the courage and strength she found in herself, and that which she saw in her fellow students. She was drawn to the idea of becoming a suited instructor, and wanted to pursue that dream. Mariko believes everybody deserves to feel safe which motivated her to work out and train to be able to become a "suit". Being a woman and openly gay, she brings a unique set of experiences and skills to her work on the mat. 
Mariko is a full-time student at Mills College where she is studying Psychology with the goal of becoming a Psychotherapist. When she isn't on the mat or studying, she enjoys walking her dogs, snowboarding, and playing the guitar and piano. She also enjoys cuddling with her cats and watching tv shows.


Drew Wheeler

Drew was drawn to Impact because of his long-standing interest in practical self-defense. He has over 10 years of martial arts experience, and a variety of colorful belts from several different disciplines. One of those belts is black.

Drew learned about Impact from a friend who had a transformative experience in the Adult Basics class. He attended the public celebration of an LGBTQ Basics class, and was mightily impressed with the techniques and scenarios he saw there. He was delighted to become a certified suited instructor in 2016, and leaves every class feeling inspired and energized by the students and by the other Impact instructors and assistants he works with.
When he's not on the mat, Drew spends time cleaning up cat hair around the house, which he shares with his wife and two cats, and occasionally his daughter when she's in town. You might also find him coaxing strange sounds from guitars and various instruments with several other Bay Area music weirdos.

Class Assistants

Our volunteer assistants provide core support for our teaching team and model Impact techniques for our students. These wonderful Impact grads volunteer their time to assist our classes because they are committed to sharing the empowerment that they experienced with new students. 

If you are interested in becoming an Impact Instructor Assistant, please click here for more information.

Our Board

The Impact Bay Area Board of Directors is responsible for our fiscal health and programmatic quality. We are always looking for qualified individuals to join Impact Bay Area's Board of Directors. Please visit the Join our Board page and fill out the form. Then email a short statement of interest and/or your resume to vanessa AT impactbayarea DOT org.  



Vanessa Baker, Board Chair

Vanessa is an enthusiastic board member of IMPACT Bay Area. A self-described "nonprofit governance nerd," she holds a Masters of Nonprofit Administration from the University of San Francisco. She joined the IMPACT board in spring 2015, eager to share her nonprofit management and fundraising expertise with an organization that so closely matched her own interests and values.
Vanessa first experienced the thrill and empowerment of learning self-defense as a 22-year-old, when a roommate suggested that she try Stanford Kenpo Karate. After 2 years as a student and then 6 more years as a student / instructor, she earned her black belt in 2013. She feels grateful for all the joy, camaraderie and self-confidence she gained through her martial arts training and loves paying it forward through her work with IMPACT.
When not volunteering for IMPACT, you can find her raising funds for Outward Bound California, where she has served as Development Director since 2012. You may also find her out hiking or biking, enjoying local theater productions, or cuddling with her two cats at her home in San Francisco.  

Jessica Pocalyko, Board Secretary

Jessica Pocalyko is a Senior Learning & Organization Development Consultant for Dignity Health, a California-based non-profit healthcare organization.  She received her Master of Science in Organization Development (MSOD) from Pepperdine University’s Graziadio School of Business and Management.  Jessica has worked extensively with non-profit organizations in both Los Angeles and San Francisco.  Jessica specializes in change management, group facilitation, cultural awareness, meeting and conference design, strategic planning, and leadership and team development. As an Impact Bay Area board member, Jessica hopes to support growth and expand community partnership while staying true to Impact’s mission and values. 


John Tudor, Board Treasurer

John joined the board in September of 2017 after attending an introductory training session with his wife. He was impressed by importance of the mission, the quality of the instruction, and IMPACT’s commitment to the empowerment of women. John was born and raised in Cape Town, South Africa, where he graduated from the University of Cape Town with a degree in finance. He left South Africa as a Rhodes Scholar to attend Oxford University where he received his MA. After working in Europe and Asia as a business strategy consultant for Monitor Company, John came to the US to attend Harvard Business School. Having graduated with his MBA, he worked for Bain Capital’s private equity fund in Boston. John left Bain Capital to join FFL, a private equity firm in San Francisco where he was until he retired. Since leaving his career in finance, John has been volunteering time at various non-profits in the Bay Area. John and his wife live in Marin with their two sons, and a Labrador.


 Stephanie Somersille, At-Large Board Member

Stephanie joined the board in May, 2018 after taking the 24 hour Basics class the previous November. She is excited about IMPACT’s mission and committed to helping as many people as possible learn to keep themselves safe and secure.

Stephanie has expertise in mathematics, finance, teaching methodologies and game theory including strategic planning. Through her consulting work, she has experience bringing varied groups together to achieve common goals.

Stephanie holds a BA in Economics from Yale University and a PhD in mathematics from University of California, Berkeley. She does math research and consults in various areas including machine learning, data science, math education and mathematical finance.

In her free time Stephanie can be found surfing, volunteering at the ballet and symphony, taking ballet classes or helping care for the animals at The Marine Mammal Center.



Monica Stone, At-Large Board Member

Monica joined the board in November 2016, motivated by her passion for empowering women and the LGBT population. She wants all people to be able to defend themselves verbally and/or physically. Monica and her two adult daughters have felt empowered by their IMPACT training and want to make the training available to everyone across the Bay Area.

Monica works as a marriage and family therapist with couples and individuals suffering from sexual difficulties as well as depression, PTSD, and anxiety. She mentors younger therapists and is active in her neighborhood organizing for carbon reduction and emergency preparedness. Monica loves bringing together her large extended family with her husband of 35 years as well as hiking, body surfing and reading about the world.



 Mary Walker, At-Large Board Member

Mary joined the IMPACT Board in February 2017 after being so impressed by the quality of the three-hour introduction class that she had to find out more about the organization behind it.Her background as both a leader in smaller technology companies and as a management consultant help her contribute at IMPACT.
Mary has worked as a Director, Vice President, and consultant to various technology companies, ranging in size from a few dozen to a few thousand employees. She has held roles in sales, customer service, business operations and human resources. She is currently associated with Exponential Talent, a boutique consulting firm that specializes in diversity and inclusion in organizations. She has a BA from Princeton University, a Masters in Anthropology from Cambridge University, and an MBA from UCLA. She lives in Redwood City with her husband Mark and enjoys photography.