Meet our experts

The Positive team thrives on differences: we have a wide range of working backgrounds and a huge breadth of experience. But there is one thing we all have in common: a passion for harnessing science to help people get the best from their brains.

Careers hero loose v2

Dr. Brian Marien


Brian started out in medicine and then became fascinated by cognitive and behavioural psychology. He worked as a specialist in the Academic Department of Psychological Medicine at St. Bartholomew’s Hospital, before co-founding Positive.

Will Marien

Co-Founder and Chief Executive Officer

Will is passionate about workplace mental health and performance and specialises in organisational behaviour change. He’s spent the last 10 years working across multiple sectors, transforming behaviours and culture in SMEs, corporate organisations, schools and universities.

Hattie Crosthwaite Eyre

Chief Operating Officer

Hattie is fascinated by human psychology and how we can get the best from our brains. She has a 1st class degree in Human Sciences from Oxford and an MSc in Public Health. She was an Engagement Manager at McKinsey, then COO at psychology start-up Potentialife.

Dr Sinéad Devine-French

Chief Product Officer

Sinead loves empowering people to think, feel and be at their best. She’s a chartered psychologist, with a wealth of experience across private, statutory and educational sectors. She has a strong interest in cognitive and behavioural approaches for sustainable change.

Dr Catherine Marshall

Delivery Director

Catherine has a clinical and academic background, having worked as both a forensic psychiatrist and university lecturer. At Positive, she combines her experience and scientific knowledge to deliver engaging and thought-provoking sessions to clients across industries.

Dr Eloise Crush

Research Director

Eloise spent the first 10 years of her career in corporate banking and management consultancy roles, before returning to her passion: psychology. Her PhD focused on psychological resilience, and she specialises in protective factors for psychological wellbeing.

Dr Ellie Smith

Research Manager

Ellie has an academic background, focusing on developmental cognitive neuroscience. Her PhD concentrated on the impact of maternal mental health on infants. At Positive, she combines her research method experience and statistical knowledge to support a data-informed journey …

Dr Alice Gee

Client Team

Alice is a Clinical Psychologist. She worked in NHS psychological services for ten years before setting up in private practice. She has a wealth of experience in the application of psychological approaches for organisations to improve wellbeing, resilience and performance.

Dr Sophia Seltzer-Eade

Client Team

Sophia is a Clinical Psychologist. She’s trained in a number of evidence-based psychological approaches, with a special interest in Cognitive Behavioural Therapy (CBT). She’s worked in a variety of clinical and business settings, and with client groups across the lifespan.

Clare Benka

Client Team

Clare has a Masters in Occupational & Organisational Psychology, and considerable experience as a consultant and coach. She runs a London clinic in physical therapies, and has a wealth of delivery experience with a wide range of organisations and corporates.

Trish Pashazadeh-Allen

Client Team

Trish is a trained Cognitive Neuroscientist with 15 years of finance and business leadership experience. She blends scientific expertise with first-hand knowledge of corporate culture, to empower businesses with strategies for positive mental health in the workplace.

Dr Tim Knowlson

Client Team

Tim is a registered and chartered Counselling Psychologist, as well as an Associate Fellow of the British Psychological Society. He has worked in UK Higher Education for over 12 years at the University of Oxford and King’s College London and has also worked within the NHS.

Dr Ellis Pecen

Client Team

Ellis is a performance psychologist with an interest in eustress and recovery strategies for optimal performance. She has over 5 years of experience working with organisations and individuals from diverse walks of life who have an interest in sustainable performance.

Dr Erica Bowen

Client Team

Dr Erica Bowen is an internationally recognised chartered psychologist, coach-mentor and government advisor. For 20 years she worked as an academic forensic psychologist, and most recently until 2020 as a full professor and senior leader at the University of Worcester.

Georgia Bolton

Client Team APAC

Georgia has a Psychology degree and almost 20 years' experience helping individuals and teams strengthen their leadership. With a special interest in the APAC region, she is passionate about building cross cultural communication and positive psychological health for leaders.

Clare Fitzsimmons

Client Team APAC

Clare is an organisational change and leadership development consultant with a background in organisational psychology. She is passionate about facilitating behavioural change that sticks and enables individuals, teams and organisations to reach their true potential.

Caro Parker

Product Manager

Caro loves supporting people to build healthy psychological skills that stick. She worked in primary and secondary schools for 15 years as a teacher and adolescent coach, and on youth product development at psychology start-up Potentialife.

Neil Thayer

Product Manager

Neil loves building technology products that customers enjoy. He joined the Positive team from a career in software architecture and product and is motivated by using technology for good. He has a keen interest of psychology and neuroscience that he applies to everything he …

Shona Wood

Marketing Manager

Shona is an English Language and Linguistics graduate with a profound appreciation for both creativity and science. She is passionate about the importance of mental health awareness and encouraging organisations to adopt a proactive approach to wellbeing.

Eleanor Hambleton-Smith

Senior Client and People Manager

Eleanor is passionate about supporting our team to thrive in their careers at Positive. She comes from a finance background, having worked in various sectors for nine years. Eleanor achieved a first class degree in her BA, Criminology with Sociology.

Rachel Vernazza

Client Success Specialist

Rachel is a qualified dentist and comes to Positive after working as both a clinician and in an educational-technology startup overseeing operational transformation. She has a keen interest in technology’s ability to do good at scale, particularly in the healthcare sector.

Alice French

Finance Administrator

Alice provides finance support at Positive and enjoys making sure the business runs smoothly. She has an MSc in Transport and Business Management and a wide range of experience working in both the public and private sectors, and with local community groups.

William Astley

Technical Operations Specialist

William provides the team with technical knowledge and gives high level support to clients. He is interested in how virtual reality might change the learning landscape, and recently completed a degree in Computer Science at the University of Kent.

Lisa McAlpine

Executive Assistant

Lisa has more than 11 years of experience providing support to senior level executives, directors and clients across multiple industries. She enjoys building and developing relationships, and thrives in a fast-paced team environment focused on client delivery.

Debbie Mack

Global Pitch Manager

Debbie has joined Positive from the Technology sector, previously working in account management and business development roles with global clients. She has an MSc in Management & Leadership and loves working with organisations to build long-term strategic partnerships.

Colm Roche

Brand and Design

Colm is responsible for the Positive brand and oversees the company’s creative output, including our website, app, online platforms and illustration. He has over 15 years’ experience, working with major international brands such as Nike, Tate, Unilever and NetJets.

Sorry, your browser is too old to support our website

Some things get better with age, but not browsers. Using an old browser can leave you and your data at risk as well as prevent you from experiencing the best of the modern web. To use our website, we'd recommend switching to one of the following: