Our leadership team is focused on building a forward-thinking company that delivers for clients and our people. Get to know them and what makes them tick.
Manjiry Tamhane
Global CEO
Manjiry co-founded Gain Theory in 2015 and was promoted to Global CEO in 2017. With a background in the practical application of mathematics in a business environment, she leverages her vast experience and expertise to transform business performance through data, technology, and advanced analytics.
Global CEO
Manjiry co-founded Gain Theory in 2015 and was promoted to Global CEO in 2017.
With a background in the practical application of mathematics in a business environment, she leverages her vast experience and expertise to transform business performance through data, technology, and advanced analytics.
Prior to Gain Theory, Manjiry was Managing Director of Ohal, a WPP company specialising in marketing effectiveness. She also worked client-side in the retail industry for over a decade.
Manjiry was named as one of the top 20 women in data in 2017 by The Female Lead and Women in Data and was included in the 100 Women to Watch list in the Cranfield School of Management’s Female FTSE Board Report in 2020.
She also serves as a Non-Executive Director at FTSE100 REIT Landsec, Co-founder of pulmonary fibrosis charity Breathing Matters, and as an Advisory Board Member at Saracens Women’s Rugby Club.
Read more: Introducing… Manjiry Tamhane
Alan Bloodworth
EMEA & APAC CEO
EMEA & APAC CEO
Alan leads our operations in EMEA and APAC where he helps clients to accelerate growth through data-informed insights.
He uses his 20 years’ experience in the marketing effectiveness industry – which included a stint as chair of technical judges for the coveted IPA Effectiveness Awards – to serve organizations from a wide range of industries and markets.
Alan is passionate about helping everyone to achieve their potential and is the executive sponsor for our DEI initiatives, including Roots, our employee-led collective of racial equity advocates.
He also dedicates time to children’s education by serving as a member of an Independent Review Panel, which helps to ensure that school exclusions are lawful, reasonable, and procedurally fair.
Read more: Introducing… Alan Bloodworth
Shawn O’Neal
Americas CEO
Americas CEO
Shawn leads our operations in the Americas from our hub in New York.
He has 30 years’ experience in building the tools, structures, and everyday practices that deliver data-informed insights to frontline decision makers at large organizations.
Shawn’s career includes more than a decade at Unilever, where he served as VP Global Marketing Data and Analytics. He has also worked as an Associate at McKinsey & Co. and in Strategic Planning for Pepsi-Cola.
Shawn has an MBA from Wharton Business School and an BA in Economics from Princeton University.
Karen Kaufman
Global Chief Strategy Officer
Global Chief Strategy Officer
Karen is focused on the application of data, analytics, and insight to deliver improved client outcomes.
She has over 25 years’ experience at WPP during which time she has provided marketing effectiveness solutions for clients from a wide range of sectors. As Managing Partner at GroupM Consulting, for example, Karen worked with a leading CPG client to develop strategies to drive long-term, profitable growth.
Data and analytics have been the cornerstone of her career. From MMM and unified measurement to scenario planning and our Marketing Effectiveness Index, Karen has expert knowledge that enables clients to make better data-informed investment decisions.
In 2021, she was recognized by Campaign US as an honoree in its 40 Over 40 list.
Monica Ziobro
Global CFO
Global CFO
Monica leads our global financial operations from our regional HQ in New York.
She joined Gain Theory in 2022 after seven years at GroupM, where she served as Finance Director. Monica also has several years’ experience in the financial services sector at firms including Cantor Fitzgerald and CohnReznik.
A certified public accountant, Monica is an accounting graduate of Montclair State University.
Sam Fellows
Global New Growth Officer
Global New Growth Officer
Sam is an experienced data, analytics, and marketing effectiveness leader with nearly 20 years’ experience across a wide range of industry verticals, notably retail, CPG, and financial services.
One of Sam’s primary roles is to work closely with new clients to ensure that the analytical frameworks and working practices that we set up deliver against key objectives and generate growth over the short and long term.
Driven by quality analysis, he takes pride in seeing how the brands we work with benefit financially from the recommendations we provide.
Sam is a published author in industry journals, has contributed to award-winning marketing effectiveness papers, and regularly sits on marketing effectiveness judging panels, such as the Effies.
Read more: Introducing… Sam Fellows
Matthew Chappell
Global Client Success Officer
Global Client Success Officer
Matt ensures clients get the right solutions, the best people, and outstanding service.
He joined as a Graduate Analyst in 2009 and became a Managing Partner in 2022.
During his career, Matt has helped brands from a wide range of industries to embed data-informed insights into their decision-making.
He has a strong econometrics background and is skilled in bringing these methodologies to life to drive organizational change.
An accomplished writer, Matt has authored several industry reports, including the award-winning Profit Ability: the business case for advertising and The nine golden rules of measurement.
He is also a regular speaker at industry events, such as Marketing Week Live and EffWorks.
Jenn Kent
Global People Lead
Global People Lead
Jenn leads our people and culture function, ensuring Gain Theory is an inclusive global community in which diverse skills, backgrounds, and passions thrive.
She has over a decade’s experience spanning critically important business processes such as operations, strategy and directional planning at companies including Jarmany, White Stuff, and Royal Caribbean Cruises.
Based in London, Jenn has an MSc Management from University of Surrey and is currently doing a Postgraduate Diploma in Executive Coaching and Mentoring at ILM.
Marc Sanford
Global Head of Data
Global Head of Data
Marc spearheads our global data strategy and leads our Data Centre of Excellence, which involves ensuring our teams have the latest training and skills they need to deliver success for clients.
He is passionate about applying industry-leading analytics and technology along with the best in social and academic sciences.
Marc has over two decades of experience in data, analytics, and insights, having held senior positions both client-side at Zillow and Expedia, and within the agency world at Razorfish and WPP.
As the Global Chief Data and Analytics Officer for WPP’s dedicated business unit for Ford, he developed a proprietary audience insights platform that streamlines data utilisation across insights, planning, activation, and optimisation.
Marc also holds the distinguished Microsoft Patent Award.
Based in Seattle, Marc has a PhD in Urban Sociology from the University of Chicago.
Jon Webb
Global Head of Advanced Analytics
Global Head of Advanced Analytics
Jon is the global head of our Analytics Centre of Excellence and leads the development of our measurement initiatives.
He has been with Gain Theory since 2000 and has extensive experience of helping clients to improve marketing effectiveness and drive profitable growth.
As brands navigate an increasingly complex world, Jon is focused on using foresight techniques that help to predict the impact of future trends and events more accurately.
Jon has been engaged within the marketing effectiveness sector for more than 35 years. Prior to Gain Theory, he was Chief Economist at NS&I, a state-owned savings bank in the UK.
An accomplished author and speaker, Jon has authored several papers on marketing effectiveness and judged numerous industry awards.
Read more: How mastering the power of foresight helps marketers to plan more effectively
Russell Nuzzo
Global Head of New Media Measurement
Global Head of New Media Measurement
Russell leads new media measurement at Gain Theory.
Passionate about reducing operational friction in the advertising ecosystem, he specializes in building highly granular marketing measurement solutions that operate in near time and deliver consistent performance.
Russell uses his more than 25 years’ experience in data and analytics to help clients make prescriptive media optimizations across partners, tactics, campaigns, and audiences, based on insights that tie back to revenue generation.
He has particular experience of the automotive, CPG, retail, e-commerce, and QSR verticals.
Russell’s career has seen him hold multiple senior analytics roles at agencies including GroupM, Mediacom, Wunderman, and RAPP.
Russell holds an MSc and BSc in Economics from Auburn University.
Read more: How granular geographic data delivers privacy-compliant insights and improves effectiveness
Brian Suh
Global Head of Products
Global Head of Products
As global product and data lead, Brian manages our product roadmap and development, as well as our overall technology strategy.
He founded the Gain Theory Data Center of Excellence to ensure a globally consistent, efficient way of working across all client engagements and created our data platform Gain Theory Data One.
Brian also works closely with WPP’s CTO Office to ensure our tech strategy aligns with that of our parent company on topics such as privacy and AI.
He blends his more than 15 years’ experience in data, analytics, and technology at consultancies, media agencies, and SaaS companies to bring a unique point of view to client challenges.
Brian holds a MEng in Engineering Management and a BS in Electrical and Computer Engineering from Cornell University.
Claudia Sestini
Global CMO
Global CMO
Claudia leads our strategic marketing and communications initiatives globally.
An award-nominated marketer, Claudia’s two-decade career spans entertainment, publishing, and digital media. She has launched, repositioned, and grown several brands, including Comedy Central, southparkstudios.co.uk, and Gain Theory.
Claudia is a passionate advocate of DEI and heads up Lumena, our global female and non-binary employee resource group, which exists to inspire, empower, and support women across our global footprint.
Claudia is a Board Advisor for two ethnic minority-owned businesses and is an Advisor for pulmonary fibrosis charity Breathing Matters.
Read more: Introducing… Claudia Sestini
Rachel Brook
Global Client Growth Leader
Global Client Growth Leader
Rachel is passionate about the power of data, analytics, and insights to accelerate business growth. Her expertise spans a range of analytic approaches, unified measurement, marketing optimization, and business impact assessment.
Prior to joining Gain Theory, Rachel gained nearly two decades of experience at MediaCom and EssenceMediacom, where she leveraged data science and business intelligence to craft comprehensive strategies and provide marketing effectiveness solutions for a wide range of businesses. At GroupM, for example, she was responsible for the agency’s advanced data, analytics, research and insights, and measurement capabilities.
Before joining WPP in 2004, Rachel held consultancy roles with a marketing analytics firm, leading predictive analytics and econometric modeling projects for various category verticals and world-class brands.
Read more: Introducing… Rachel Brook
Arvind Sethumadhavan
Client Growth Officer, APAC
Client Growth Officer, APAC
Arvind is a marketing, innovation, data, analytics, and AI expert who has over 25 years’ experience working with large global brands across a range of sectors.
Based in Singapore, he works with ambitious companies across APAC to help transform their marketing operations.
Arvind has in-depth knowledge of new technology adoption trends, digital consumer habits, media behavior, the ad and martech landscape, and e-commerce.
He is a mentor at the Singapore Management University’s Institute of Innovation and Entrepreneurship and has helped over 100 start-ups to improve their growth marketing strategies.
Prior to joining Gain Theory, Arvind held senior leadership roles at companies such as Kantar, GroupM, and Dentsu International, where he launched their first Global Data Innovation Centre to leverage the power of AI.
Read more: Introducing… Arvind Sethumadhavan
Felix Bullinger
Senior Client Leader
Senior Client Leader
Felix applies his passion and experience in analytics to help businesses drive growth and improve marketing ROI.
He delivers this to our EMEA- and APAC-based clients by leading a multi-market team of data scientists, analysts, and consultants.
Felix brings over 25 years of knowledge in developing and executing effective media strategies, growing brand and business for many global clients.
Prior to joining Gain Theory, he held senior client-facing positions at media networks including dentsu, GroupM, and Omnicom.
Felix is a German national who has lived and worked in London since 2005.
Lindsay Egan
Senior Client Leader
Senior Client Leader
Lindsay leads client strategy on several marketing effectiveness projects, helping brands from a range of sectors to make faster and smarter business decisions.
She’s a passionate advocate of building and integrating measurement solutions into large corporations and championing test and learn cultures.
Lindsay also leads culture activities for our people across North America, helping to build a sense of community across our remote workforce.
Her career has seen her build marketing measurement strategies at brands such as Target and Best Buy, where she embedded market mix models and attribution tools.
Lindsay is based in Minneapolis and has an MBA and a BS in Business Administration.
Read more: Introducing… Lindsay Egan
Justin Nel
New Business & Client Engagement Director, Australia
New Business & Client Engagement Director, Australia
Justin uses his extensive experience in research, analytics, and insights to lead client engagement across Australia.
He joined Gain Theory in 2024 from Circana, where he served as Commercial Director, Analytics and Media. Prior to this, he spent over a decade working at companies including Mintel, Acxiom, and Nielsen.
Justin has worked with a wide range of brands from a variety of sectors, such as banking, CPG/FMCG, tech, telecoms, and travel.
Based in Sydney, he works closely with our Client Growth Officer for APAC in Singapore, as well as the wider Gain Theory teams in Europe and the Americas, to help Australian brands accelerate growth through marketing effectiveness.
Read more: Introducing… Justin Nel
Akhila Venkitachalam
Senior Client Leader
Senior Client Leader
Akhila uses her more than 20 years’ experience in analytics and consulting to lead some of our largest client engagements and support new business growth.
She works with senior marketers at global brands in various sectors to improve ROI measurement programs, budget allocations, brand analytics, forecasting, and pricing and promotion strategies.
Akhila is also part of our Best Places to Work team, helping to create a brilliant work environment for all our colleagues.
Prior to joining Gain Theory, Akhila led advanced analytics consulting at Kantar and Nielsen where she worked with numerous national and global brands.
She has spoken at several industry events, contributed to academic research at London Business School, and holds an MBA and a BTech in Electrical Engineering.
Read more: Introducing… Akhila Venkitachalam
James Dodge
Senior Client Leader
Senior Client Leader
James is passionate about helping clients solve challenges with the right data, technology, and analytics.
Based in Chicago, he has 30 years’ experience in consulting and advanced analytics for the CPG, retail, QSR and insurance industries.
Prior to Gain Theory, James built and lead Nielsen’s Retail Consulting & Analytics practice, and has also worked for BASES, McKinsey and Milliman.
He has an MBA from the University of Chicago Booth School of Business and a BS from DePaul University. James is also the co-author of a US patent for an analytical process.
Read more: 3 ways marketers can combat uncertainty and build confidence
Joe Wilkinson
Senior Client Leader
Senior Client Leader
Joe leads Gain Theory’s innovation, technical and product teams, overseeing the development of our proprietary modelling software and advanced analytics platform ROVA, as well as several client engagements.
With over a decade’s experience in delivering marketing effectiveness projects across Europe and North America, Joe provides innovative solutions for our clients in the retail, e-commerce, and recruitment sectors.
He joined Gain Theory as a Trainee Analyst in 2010 and was made a Senior Partner in 2021.
Joe has a BSc in Economics from the University of Sheffield.
Jon Bardelli
Senior Client Leader
Senior Client Leader
Jon has over 15 years’ experience in business driver measurement and advanced analytics.
He works with many of our largest clients, helping them to drive growth and efficiencies across media channels.
Prior to joining Gain Theory, Jon worked at several leading analytics firms and media agencies where he specialized in CPG and healthcare, among other verticals.
Based in Connecticut and working out of our New York office, Jon also leads recruiting and talent acquisition for Gain Theory North America.
He graduated from Central Connecticut State University with a BA in Marketing.
Denise Green
Finance Director, EMEA & APAC
Finance Director, EMEA & APAC
Denise leads the EMEA finance team in London where she oversees financial operations, reporting, and planning.
She joined Gain Theory as Financial Controller and became Finance Director in 2019. Denise has also collaborated with Wunderman Thompson, another WPP company, to spearhead several female wellbeing initiatives.
An ACA qualified accountant, she has spent 20 years gaining extensive finance experience across a range of sectors including retail and hospitality, as well as at the operator of the UK National Lottery.
Denise has a BSc in Business Studies with International Business from the University of Salford.
Chris Chumun
Senior Client Leader
Senior Client Leader
Chris has over 19 years’ experience in delivering and scaling advanced analytics solutions for clients in FMCG, retail, entertainment, fashion, auto, utilities, pharma, travel, finance, and technology.
A specialist in brand optimisation and marketing effectiveness, he has also worked extensively on segmentation, customer satisfaction, concept testing, panel data, data fusion, and ad targeting.
In addition to his day-to-day work, Chris plays a key role in Roots – our employee-led collective of racial equity advocates.
He holds a BSc in Computer Science from Nottingham University, an MSc in Operational Research from Lancaster University, and an MSc in Applied Statistics from Sheffield Hallam University.
Read more: Introducing… Chris Chumun
Maria Fadeeva
Senior Client Leader
Senior Client Leader
Maria is a CPG specialist who works on some of our largest accounts in that sector.
Her expertise in econometrics, predictive and statistical modeling, and market mix modeling, helps brands to grow by making their marketing more effective.
Maria joined Gain Theory in 2017 and has over 15 years’ experience in the data and analytics industry having worked at a number of agencies and consultancies.
Based in Florida, she helps to train people who are starting their Gain Theory careers in areas such as data, media, and modeling.
Maria has an MA in Economics and Mathematics from New York University.
Read more: Introducing… Maria Fadeeva
Aleksandr Feygis
Senior Client Leader
Senior Client Leader
Aleksandr has 15 years’ experience in helping brands to deliver profitable growth using advanced analytics.
Since joining Gain Theory in 2018, he has led measurement programs for clients across multiple industries, including CPG, DTC/e-commerce, and entertainment.
Previously, he worked at companies including GroupM and Accenture where he developed measurement programs that drove significant value for clients in a wide range of verticals.
Based in our New York office, Aleksandr also leads presentation development training for all our people in North America and is an integral part of our social committee.
He has an MA in Economics from Boston University.
Read more: Introducing… Aleksandr Feygis
Yulia Shutko
Senior Client Leader
Senior Client Leader
Yulia is a marketing and data technology consultant who helps global clients to understand their marketing performance and drive growth.
She has over 10 years’ experience in modelling, budget optimization, CRM, and campaign analysis across various sectors including finance, FMCG, and retail.
As well as delivering data analytics projects for clients, Yulia also leads our internal promotion boards and Managers’ Academy in EMEA.
She joined Gain Theory in 2022 after working at agencies in London and Singapore where she managed multiple accounts across EMEA, APAC, and LATAM.
Yulia holds an MA in Entrepreneurial Management and a BA in Management and Business.
Read more: Introducing… Yulia Shutko
Marina Stuefer
Senior Client Leader
Senior Client Leader
Marina leads client engagements from San Francisco, an office she set up in 2017.
With 12 years’ experience in advanced analytics, Marina helps organizations to turn data into actionable insights that build sustainable business growth.
She enables clients to understand business drivers and consumer interactions with their brand, forecast multi-year returns from investments, course-correct activities on strategic and tactical levels, and optimize marketing, media, promo, and pricing strategies.
Marina has led multi-country client engagements in DTC/e-commerce, cryptocurrency, QSR and casual dining, retail, and finance.
She is also the proud founder of Lumena, our employee resource group that inspires, empowers, and supports women and non-binary people to maximize their potential.
Marina holds an MS in Economics and a Postgraduate Diploma in Data Science.
Tony Neville
Senior Client Leader
Senior Client Leader
Tony leads our Sensor modelling team in EMEA, enabling clients to understand marketing and media performance at a highly granular level of detail.
He also leads several client engagements with a particular focus on the e-commerce and online finance industries.
Tony has many years of experience in the marketing analytics industry having joined Gain Theory as a Graduate Analyst in 2004. He was made a Partner in 2017 and is a key member of the company’s social committee in EMEA.
Tony has a BSc in Economics and Econometrics and an MSc in Economics from the University of Nottingham.
Andrew Bertolaso
Senior Client Leader
Senior Client Leader
Andrew is a Senior Partner who has extensive experience in the marketing effectiveness industry.
He has a global remit with one of our largest clients and was part of the team that was recognized with the IPA Gold award for creating an outstanding culture of marketing effectiveness.
Andrew has specialist knowledge of the alcoholic beverages market but has worked with clients across a range of sectors, including aviation, consumer electronics, financial services, pharmaceuticals, and retail.
He is an active member of the City of London Round Table for whom he enjoys fundraising.
Andrew holds an MA in Economics from the University of St Andrews and an MSc in Economics from the University of Warwick.
Patricia Moro
Senior Client Leader
Senior Client Leader
Patricia leads client leadership and business development for Spanish- and Portuguese-speaking markets around the world.
She is passionate about helping clients in countries such as Spain and Brazil to make smarter, faster data-informed decisions.
Patricia joined Gain Theory in 2017 after 11 years at consulting firm Bayes Forecast. She also has a background in human resources, having served as People and Talent Director at the Spanish National Research Council and as HR Manager at Grupo Damm.
Patricia has a number of academic qualifications, including an Executive Master’s in Management from IE Business School, a PhD in Management and Business from Universidad Rey Juan Carlos, and a degree in Psychology from Salamanca University.