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Mea Blackmon,

Operations Specialist &

Executive Assistant


Daniel Mangelsdorf, Managing Partner


Daniel Mangelsdorf is the Managing Partner for SDI Communications. Dan draws on his breadth of first-hand leadership experience in Operations, Sales, Marketing, New Product Development and Information Technology to bring informed and unique insights to clients. He has extensive experience in a wide range of functional areas across industries, as well as advising large global and small entrepreneurial companies.


Prior to joining SDI in 2002, Dan spent 12 years in the high-technology industry. He was Vice President, Global Marketing for the Service Provider Voice Business, at Nortel Networks, a telecommunications equipment supplier. His business unit brought in four billion per year in revenue. In that leadership role, he dealt with maximizing revenue and profit contribution from a mature business, while simultaneously innovating and building new product lines. During his 5-year tenure, Nortel became a market leader for the next generation of voice switching equipment. He was also a steering committee member of Nortel’s leadership development program and a mentor in the female executive mentoring program.


Before joining Nortel, Dan held several senior leadership positions with NetEdge Systems, a technology startup, which included responsibility for new product introduction, global planning, logistics and sales engineering. He also held positions in Operations, Supply Chain and Manufacturing at Solectron, Baker Oil Tools and Sun Microsystems.


Dan graduated with an M.B.A from Rice University and a B.S. in Management from Santa Clara University. He lives in the Research Triangle Park area of North Carolina with his wife and has three children.

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Liza Herschel, Partner


Liza Herschel is a Partner for SDI Communications. Liza draws on an extensive background both in education and marketing and an applied practice of leadership and high-performance consulting in a wide range of industries and functional areas.


Prior to joining SDI in 2007, Liza was Senior Director at ZAMWorks, a marketing and media firm based in New York City. She was the primary liaison to zoos, aquariums and other nature-based groups throughout North America, Europe, Africa and the Philippines. She also directed the development and national distribution of a unique conservation curriculum for middle school students. During her 7-year tenure at ZAMWorks, she coached and developed staff to run the program she created.


Before joining ZAMWorks, Liza was Assistant Director, Conservation Education, at the American Zoo and Aquarium Association. She coordinated the national-level professional activities and development of conservation educators in accredited zoos and aquariums throughout North America. She also held positions in various educational roles at several zoos, including Curator at the Baltimore Zoo for six years.


Liza did her graduate studies at Antioch University in Environmental Education and graduated with a B.S. in Political Science from Brown University. She lives in Philadelphia, PA, with her husband and has two daughters.


Judy List, Principal Consultant

Judy List is an Executive Consultant for SDI Communications after being a client of the firm for more than 12 years.


Prior to joining SDI, Judy spent 30 years in the consulting, telecommunications and information technology industries. She held executive positions at IBM, Unisys, BearingPoint (formerly KPMG Consulting) and Telcordia (formerly Bellcore). She led large, global organizations through major transformations while delivering consistent financial results. She helped her clients improve financial performance through the strategic use of technology across a variety of functional areas. These ranged from advanced marketing analytics, customer care, product development, large-scale systems integration of financial, HR and supply chain functions, to strategic outsourcing of IT and business processes. Her efforts always addressed the leadership needed to achieve results in dynamic and changing environments.


Judy’s early career was in academia as an Assistant Professor of Psychology at Clark University where she shared her expertise in growth and development.


Judy graduated with a Ph.D. in Developmental Psychology from the University of Minnesota and a B.A. in Psychology, Human Development and Family from the University of Kansas. She lives in Park City, UT, with her husband and has three children.

Jonathan Clark, Principal Consultant


Jonathan Clark is a Consultant for SDI Communications. Jonathan brings three decades of experience guiding top executives, professionals and entrepreneurs in elevating their individual effectiveness for organizational success.


Jonathan has worked with visionary business leaders across industries from Panera Bread and Friendly’s Ice Cream to American Express and Western Union to bring out the creativity, talent and collaboration of their people in ways that catapult their companies to optimal performance.


Jonathan has also brought his expertise to producing breakthrough charity events, resulting in his “Point of Light” presidential designation and recognition as “Person of the Week” on ABC World News Tonight for his contribution to the mission of ending world hunger.


Prior to becoming a consultant, Jonathan was a sports coach, which has enabled him to convey a unique perspective on the art and science of human action and interaction. He has had years of training in understanding human behavior.


Jonathan graduated with a degree in Structural Engineering from Hartford State Technical College. He lives in Tampa, FL, with his wife and has two daughters.

Julian Serrao, Senior Consultant


Julian Serrao is a Senior Consultant for SDI Communications. Julian draws on seven years of first-hand leadership experience in the education sector.


He ran a business consulting with firms, design labs, non-profits and education technology startups on a broad array of private, public, national, regional and local initiatives ranging from developing an in-district K12 innovation lab to planning a collective impact hub for student advising.


Much of his work has been geared toward expanding education access in underserved communities, including driving strategy for a startup tackling low-income public school enrollment as a part of the LearnLaunch innovation cohort.


Prior to consulting in education, Julian was a teacher who incorporated new blended learning models and created a process and context in which traditionally underserved students co-created their math learning pathways and adapted Agile processes to achieve desired outcomes.


Julian graduated from Yale University with a B.A. in Anthropology. He lives in Cambridge, MA.

Alexa Rogers, Consultant


Alexa Rogers is a Consultant for SDI Communications. Alexa brings nearly a decade of experience in transformation, project management, program development, and developing and executing conferences and trainings both in-person and on Zoom.  


Previously, Alexa was a social media manager and consultant for seven years managing social media accounts for national brands and individuals.  Alexa has 12 years of graphic design expertise and owns her own social graphic design company creating promotional material and content to fit client needs.


​Alexa graduated with a B.S. in Business Management with a Minor in Spanish Linguistics and an International Business Certificate from Arizona State University. She lives in Southern California when not travelling.

Ash M. Straw, Consultant


Ash M. Straw is a Consultant for SDI Communications who brings nearly a decade of experience designing, developing, and delivering transformational leadership conferences and training programs to her role. 

Ash is passionate about making online learning content available and has consulted as a course content designer, builder, and manager for educators who have provided thousands of masterclass-style courses to over 3 million students worldwide.  Prior to joining SDI, Ash also designed and delivered advanced yoga programs and yoga teacher trainings with her company at the time, Flow and Restore.


Ash lives with her partner Timothy in the Hudson Valley of New York State and performs in local theater in her spare time.

Timothy O'Malley, Consultant


Timothy is a Consultant for SDI Communications. He has twenty years of experience and has delivered transformational programs to thousands of people.  

Timothy has extensive leadership and coaching experience developing teams to be exceptionally high achieving, contributing to multi-million dollar annual positive impacts to the bottom line. 

Before joining SDI, Timothy worked in various operations and sales roles for several companies, including an industry-leading, multi-national corporation. He often specialized in "turnaround" assignments, taking underperforming teams to a level of high performance.

Timothy studied Philosophy and Social Welfare at the University of Kansas. Timothy has two children and currently lives in New York's Hudson Valley. 



Doreen Del Col, Operations Manager


Doreen Del Col is an Operations Manager for SDI Communications. Doreen brings more than 30 years of management experience and contributes a rich background in organizational and interpersonal skills. She has a deep passion for transformational work both personally and professionally.


Prior to joining SDI in 2004, Doreen was Vice President, Institutional Investment Group, at PNC Bank where she was responsible for maintaining the business relationships of over seventy-five high net-worth clients. She also held positions in Senior Operations and Administration at Irving Trust Company and First Fidelity Bank.


Doreen graduated with a B.S. from St. John’s University. She lives in the greater New York City area and has two sons.

Dana Rojas, Executive Assistant


Dana Rojas is an Executive Assistant for SDI Communications’ senior consulting team. Dana brings more than 20 years of administrative and executive support experience. She contributes her organizational and meeting planning skills, having successfully coordinated events for 100+ employees.


Prior to joining SDI in 2016, Dana was Executive Assistant for senior management in sales and marketing business units at Ricoh Corporation, a business service company that offers document management and digital printing solutions.


She lives in central New Jersey with her husband and daughter.

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Mea Blackmon, Operations Specialist & Executive Assistant

Mea Blackmon is an Operations Specialist & Executive Assistant for SDI Communications’ senior consulting team. Mea contributes organizational and problem-solving skills from her experience in executive and administrative support roles.  


Before joining SDI, Mea was an Executive Assistant to the Vice President of Operations at The Fragrance Outlet, a retail business specializing in designer fragrances.


Mea graduated from the University of North Carolina at Greensboro with a B.S. in Business Administration, minoring in Marketing, and is pursuing postgraduate studies in Data Analytics at the University of North Carolina - Chapel Hill. She lives in the Research Triangle Park area of NC.

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