Effectiveness & Testing Director in London

Company description Performics UK is the performance marketing arm of Publicis Media, committed to exceeding business goals by blending Data, Tech, Ops, and Talent to accelerate performance impact daily. With over two decades of experience, we harness technology and innovation to generate and convert consumer demand across search, social, display, and commerce channels. Embracing a deep understanding of consumer intent and behaviour, we thrive on data‑driven insights, guiding our planning and optimisation processes through rapid trials, real‑time enhancements, and intelligent analytics. As the world’s first Performance Orchestration agency, we have a proven track record of driving performance impact across diverse sectors and markets, leveraging our industry expertise to innovate and transform swiftly. Performics is dedicated to delivering award‑winning results and empowering all Publicis Media UK clients.

Overview As a Measurement & Growth Science Lead within NextLab, you will play a critical role in shaping how effectiveness, testing and measurement best practice is defined and embedded across the Sky account. Sitting within the Measurement & Growth Science team, you will report into the Measurement Lead, while working extremely closely with Media Planning, Vertical Planning teams and Digital Leads. Your role is to act as a strategic partner and technical challenger; ensuring that experimentation, measurement design and data foundations are robust, practical and decision‑led. This is not a pure analytics role, nor a traditional planning role. Instead, it requires someone who can:

• Zoom out to understand the full media ecosystem and business context;
• Zoom in to challenge how tests are designed, how data is structured, and whether measurement approaches will genuinely answer the questions being asked.

You will help ensure that Sky’s investment in media is underpinned by clear learning agendas, high‑quality experimentation, and trusted sources of truth, while enabling planning teams to move faster and more confidently.

Responsibilities Effectiveness & Experimentation Leadership Act as a partner to Sky stakeholders and Publicis planning teams on measurement, effectiveness and test‑and‑learn strategy. Shape and challenge experiment design (e.g. incrementality studies, conventional tests, controls and splits), ensuring approaches are feasible, statistically sound and decision‑useful. Partner closely with Vertical Planning teams and Digital Leads to embed best‑in‑class testing practices across Brand and Performance activities. Support the definition of learning agendas – ensuring tests are connected to clear business questions rather than activity for activity’s sake.

Cross‑Team Enablement & Partnership Act as a bridge between measurement teams, media planners and channel specialists, translating technical considerations into practical planning implications. Serve as an active thought partner – confidently challenging assumptions and helping teams stress‑test ideas before they go live. Support Digital Leads and Vertical Planning teams by providing clarity on what good looks like when it comes to effectiveness and testing. Contribute to the development of shared ways of working, templates and playbooks that improve consistency across teams.

Operational & Knowledge Enablement Support the ongoing standardisation of measurement frameworks, trackers and reporting processes, working alongside NextLab colleagues and planning leadership. Help document and codify best practice (e.g., “Best practices for implementing Brand Lift Surveys to support your measurement strategy”), ensuring knowledge is transferable and scalable. Identify gaps in capability or process and help shape solutions that improve speed, quality and confidence across the organization.

Measurement Foundations & Data Integrity Champion initiatives that improve data integrity, consistency and clarity, including: Single Source of Truth for spend and planned budgets. Conversion tracking and reporting consistency. Alignment between platform, ad‑server and first‑party data. Help simplify complex data landscapes without losing meaning, balancing granularity vs. usability for decision‑makers. Work closely with your NextLab colleagues, tagging and analytics partners to ensure measurement outputs are credible, trusted and actionable.

Qualifications The successful candidate will be a strategic, analytically minded practitioner who combines hands‑on channel understanding with the ability to challenge and improve how effectiveness is measured at scale. This role suits someone who enjoys operating in ambiguity, influencing without direct authority, and working at the intersection of media planning, data and experimentation.

Must Have Experience in a measurement, effectiveness, strategy or growth‑focused role within media, consulting or a complex client environment. Strong understanding of media experimentation and test design, including incrementality, attribution considerations and performance measurement. Hands‑on experience from at least one paid media channel background (Paid Social, Programmatic, Paid Search, etc.), with an appreciation of how channels interact. Ability to challenge measurement approaches constructively, balancing technical rigour with commercial pragmatism. Strong stakeholder management skills, with confidence working alongside senior client and agency leaders. Excellent communication skills – able to translate complex measurement concepts into clear, actionable guidance. A critical thinker with a proactive, solutions‑oriented mindset.

Ideally Have Experience working with or alongside Growth Science, Analytics or Marketing Science teams. Familiarity with measurement approaches such as attribution, MMM, brand lift studies, incrementality testing and learning agendas. Exposure to large, complex advertisers (e.g. telco, entertainment, subscription‑based businesses). Experience contributing to data standardisation, reporting frameworks or operational best practice. Interest in how emerging tools, AI and automation can enhance measurement and experimentation.

Additional information Publicis Media has fantastic benefits on offer to all of our employees. In addition to the classics, Pension, Life Assurance, Private Medical and Income Protection Plans we also offer:

• WORK YOUR WORLD – opportunity to work anywhere in the world, where there is a Publicis office, for up to 6 weeks a year.
• REFLECTION DAYS – Two additional days of paid leave to step away from your usual day‑to‑day work and create time to focus on your well‑being and self‑care.
• HELP@HAND BENEFITS – 24/7 helpline to support you on a personal and professional level. Access to remote GPs, mental health support and CBT. Wellbeing content and lifestyle coaching.
• FAMILY FRIENDLY POLICIES – We provide 26 weeks of full pay for the following family milestones: Maternity, Adoption, Surrogacy and Shared Parental Leave.
• FLEXIBLE WORKING, BANK HOLIDAY SWAP & BIRTHDAY DAY OFF – You are entitled to an additional day off for your birthday, from your first day of employment.
• GREAT LOCAL DISCOUNTS – This includes membership discounts with Soho Friends, local restaurants and retailers in Westfield White City and Television Centre.

Full details of our benefits will be shared when you join us! Publicis Groupe operates a hybrid working pattern with full‑time employees being office‑based three days during the working week. We are supportive of all candidates and are committed to providing a fair assessment process. If you have any circumstances (such as neurodiversity, physical or mental impairments or a medical condition) that may affect your assessment, please inform your Talent Acquisition Partner. We will discuss possible adjustments to ensure fairness. Rest assured, disclosing this information will not impact your treatment in our process. Please make sure you check out the Publicis Career Page which showcases our Inclusive Benefits and our EAGs (Employee Action Groups).