Tammy Wallace
“Tammy's biggest achievement is helping to turn around Which?'s most complex multi-year digital migration project”
Part of the Tech Women Celebration 50, a curated list of some of the most inspirational women working at all levels of tech
Tammy Wallace is a product leader with more than 15 years' experience in digital product management, programme leadership and operational transformation across the public sector, consumer brands and digital consultancy.
She joined UK consumer organisation Which? as Product Lead in January 2025. Her career includes central government roles at the Ministry of Justice and DEFRA, work with consumer brands LEGO, Avios and Sony PlayStation, and positions at digital consultancies Hippo Digital and Digitas LBi. This breadth of experience informs how she builds products for different organisations. At LEGO, she led the launch of the LEGO Insiders membership programme and managed its CRM product setup.
At the Ministry of Justice, she led the redesign and implementation of the National Probation Digital Service. She holds a Certificate in Senior Leadership from Henley Business School and a mediation accreditation, combining human-centred design, stakeholder engagement and operational rigour to build effective digital services.
Tell us about the nominee's biggest achievement to date
Tammy Wallace's biggest achievement is helping to turn around Which?'s most complex multi-year digital migration project. Joining midway through the programme, she revitalised the team, rebuilt organisational trust and completed the legacy overhaul. Her team has since replaced core technology stacks, launched new gifting services and established a prioritisation process that has been adopted across the company.
The work reflects her philosophy of making digital transformation practical and ensuring organisations build products that work for people.
The programme also supported company revenue growth for two consecutive years. Which? Commercial Director Phil Amy describes her as a "breath of fresh air" whose collaborative approach connects technical and commercial teams. He adds: "I have been inspired by how she juggles the demands of prioritising cross-functional activity, whilst ensuring her team and those that work with her are motivated." By combining commercial focus with human-centred leadership and advocacy for women in tech, Tammy improved both project delivery and the organisation's wider delivery culture.
What is the most significant challenge the nominee has overcome?
Tammy's most significant challenge has been leading digital transformation across legacy systems by bringing cross-functional teams together. At LEGO, she helped her teams increase the CRM audience by 20% and the engaged base by 38%. She brought that experience to Which?, where fragmented product and B2B architecture required both technical change and organisational alignment.
Her team improved Apple Pay to deliver a significant uplift, moved away from legacy platforms and is developing an automated, API-first B2B architecture. Tammy credits these results to the engineering, data and product specialists working towards a shared vision, supported by her empathetic, human-centred leadership.
Tell us something about the nominee people would find surprising
Tammy spent ten years studying in France, from her teenage years into her early twenties, before establishing her career in UK technology and public-sector delivery. Moving between languages and education systems taught her not to assume that everyone shares the same reference points, an instinct that is valuable in large cross-functional programmes.
She is also an accredited mediator, trained through the London School of Mediation. That training strengthened her ability to help people with different views understand each other and reach agreement. In technology delivery, she applies the same approach when aligning engineering and policy teams on scope or helping a board navigate a difficult decision: slow down, understand what each side needs and find a workable way forward.