Leadership Team

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Sonja Kresojevic

Originally from Belgrade, Sonja’s career has taken her from the UK to Canada, Silicon Valley and to New York where she now lives with her two children.

Sonja has 20 years of global experience as a senior executive building products and driving agile and lean transformation inside large enterprises including Channel 5, News UK, BBC and Unboxed

Passionate innovation strategist who understands what it takes to bring Lean startup and Agile into the enterprise. 

Most recently Sonja was SVP in the Chief Product Office at Pearson, leading the implementation of the award winning Global Product Lifecycle.

You can find Sonja's full profile on Linkedin

Jonathan Bertfield

Jonathan hails from Manchester in the UK and has lived in Jerusalem, San Francisco, and now Brooklyn where he lives with his wife, 3 children and his dog Quincy. 

Jonathan has over 20 years of leadership roles in product organizations at large enterprises and startups including Scholastic, Pearson, Peroozal, Readio and Sesame Workshop.

Since the mid 00’s Jonathan has been a Consultant, coach and workshop facilitator focused on Lean Enterprise, Agile mindset and Product Management best practice.

He is a Senior Faculty at Lean Startup Co and General Assembly Enterprise as well as a coach and Mentor at NYU’s Stern Annual Business Plan Competition

Consulting clients include Pearson, US Department of Defense, Legal Zoom,  Marriot, Axa, USAA, K12, Citibank, News Corp, & Associated Press,


You can find Jonathan's full profile on Linkedin

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Our Extended Team

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Adam Berk

Adam has traveled the world mentoring, teaching, consulting and coaching teams and individuals at places like KauffmanLabs, TechPeaks, Bizdom, Numa Paris, StartupIstanbul, Startup Chile, TurkishWIN, FastForward Ramallah, AOL, ESPN, NEWSCORP, AMEX and others who don't want their competition to know just how valuable it can be to run the types of experiments he teaches.

You can find Adam's full profile on Linkedin





Sam has helped numerous technology product teams to be successful and deliver meaningfully for their businesses, consulting with both startups and established companies. Past clients include Adobe, Sharethrough, and Blackstone Charitable Foundation. He has long been an active member of the Agile and Lean Startup communities of practice in the Bay Area. He is the author of Startup Patterns (2016), and writes and speaks regularly on the intersection of product development and society.

You can find out more about Sam on his site Startup Patterns