The opportunity:

A commercially astute and consultatively minded Client Success Partner to join our client leadership team. This is a senior advisory role at the heart of how we create value for our clients — translating complex analytical work into strategic guidance that directly shapes our clients' investment decisions and growth trajectories. 

You are a trusted advisor first and foremost — someone who builds genuine partnerships with senior client stakeholders, earns a seat at the table through deep expertise, and brings the intellectual curiosity and commercial instinct to identify where Gain Theory can make a meaningful difference. 

You will bring 12+ years of experience in marketing effectiveness, analytics, or a related consulting discipline. 

What you’ll be doing:

• Acting as a Strategic Advisor to Senior Clients: You'll be the primary consultative voice for your clients — proactively shaping how they think about marketing investment, effectiveness measurement, and growth. You won't wait to be asked; you'll bring forward-looking perspectives, challenge assumptions constructively, and connect analytical findings to real business outcomes. Your clients will value you as a partner who understands their world as much as you understand ours. 

• Translating Complexity into Strategic Clarity: You'll take sophisticated analytical outputs (MMM, attribution-like techniques), scenario planning) and craft compelling narratives that resonate with senior decision-makers. Your ability to distil complexity into clear strategic recommendations will be central to the value clients associate with Gain Theory. 

• Shaping the Consulting Agenda: You'll lead strategic client conversations, facilitate workshops, and contribute to thought leadership that keeps Gain Theory working at an elevated level with our clients. You'll bring genuine intellectual curiosity to your clients' industries, anticipating trends and advising on where measurement and investment strategies need to evolve. 

• Identifying and Developing Client Opportunities: Through deep understanding of your clients' challenges and ambitions, you'll proactively identify where expanded consultancy can add value — growing relationships organically through relevance and trust. You'll lead new business conversations and pitches with authority and credibility. 

• Enabling a High-Performing Consultancy Team: You'll lead and mentor a team of five (plus broader dotted-line relationships), fostering a consultative culture built on intellectual rigour, client empathy, and continuous learning. You'll ensure delivery quality remains high while developing your team's ability to think and communicate like trusted advisors. 

What we want from you:

• Analytics Consultancy Expertise: A proven track record of advising senior stakeholders, framing complex problems, and delivering recommendations that influence real strategic decisions. 

• Deep Analytical Fluency: The ability to engage meaningfully with sophisticated analytical methodologies such as MMM, lift tests and attribution, translating them into clear, actionable strategic narratives for non-technical audiences. 

• Trusted Relationship Building: Demonstrated success in developing genuine, long-term advisory relationships at C-suite and senior marketing leadership level — built on credibility, candour, and consistently delivering value. 

• Strategic & Commercial Acumen: Experience identifying growth opportunities through consultative insight, with a strong understanding of how to articulate and demonstrate value in a professional services context. 

• Industry Knowledge & Intellectual Curiosity: Deep grounding in marketing effectiveness and analytics, combined with a genuine interest in clients' industries and an ability to connect broader market trends to client-specific challenges. 
• Values Alignment: A natural alignment with core values: Be Curious, Be Positive, Act with Consideration, and Make it Better. 

Your Impact Will Be Measured By: 

• Depth and quality of strategic advisory relationships with senior client stakeholders 

• Demonstrable value and strategic influence delivered to clients 

• Exceptional client satisfaction (Performance, Preference, Likelihood to Recommend) 

• Achievement of net sales growth targets through consultative opportunity development 
• High satisfaction and consultative capability growth within your Client Success team 

Key Relationships You'll Build: 

• Senior client stakeholders (Marketing Directors, CMOs, Insights and Strategy leads) 

• Client Success Group & Executive Leadership Team 

• Gain Theory's Data, Analytics and Operations community, plus New Business and Strategy teams 

Location: 

Ideally London, with an expectation of 2–3 days in Gain Theory and/or client offices. 

Why work for us? 

Gain Theory is committed to actively building a diverse, equitable and inclusive workplace where everyone feels welcomed, valued and heard, and is treated with dignity and respect.  As leaders and creative partners across industries, it is our responsibility to cultivate an environment reflective of our greatest asset; our people. We believe that this commitment inspires growth and delivers equitable outcomes for everyone as well as the clients and communities we serve. 

What we pride ourselves on: 

• Growth and development
• Meaningful work
• Flexible by design
• Brilliant benefits 
• Culture with Heart

Our exceptional and skilled team defines Gain Theory. That's why we seek individuals who strive for excellence and continually challenge us to improve.

What we do 

Gain Theory is a global marketing effectiveness and foresight consultancy. Our vision is to accelerate growth for ambitious brands by giving clients the confidence to make better data-informed investment decisions. High-touch consultancy powered by unique partnerships and proprietary technology are used to power our award-winning solutions.  

 As a WPP consultancy, Gain Theory also has access to a range of data, expertise, and tools that create a truly differentiated offering. 

 Gain Theory is a WPP agency (NYSE: WPP).      

 Who we are 

We are a people-centric organisation whose culture is underpinned by 4 important values: Be Curious, Be Positive, Make it Better and Act with Consideration. We channel these values through our behaviours, in the way we work, and in the interactions we have with each other and our clients. 

The opportunity:

You will support senior colleagues in achieving the efficient delivery of client projects. Typical responsibilities and duties are the collection and preparation of data, contributing to the finalisation of models, writing results and implications and SFX creation.

Your role as Principal Analyst is to take responsibility for and oversee other analysts. You will also be expected support the development of analysts through the Training Academy, Knowledge Shares and feedback. Principal Analysts should develop relationships with their counterparts client side and be able to communicate Gain Theory approaches and brand beliefs.

What you’ll be doing:

Working with data: Data extraction and manipulation, data analysis and validation, batch files, programming

• Undertake data extraction, manipulation, and data analysis to understand the marketplace and client context relevant to each project.
• Analyse all datasets to ensure that each KPI is understood and can be explained back to the team.
• Ensure that all tables, charts and other information produced by you, or others has been checked for accuracy and formatted to GT standards before passing on to senior project team.
• Be responsible for data collection including preparation and sending of data requests, chasing outstanding data and querying data with clients and agencies.
• Ensure that ROVA input files are structured to meet requirements of project (e.g. order and number of variables, exclusion of unnecessary variables)
• Ensure that all outputs are checked for accuracy by analysts; record any checks made.
• Proficiency in using data extraction tools (i.e. Advantage, AdDynamix, Sysomos, Google Trends, Google Analytics, Double Click) and able to teach others in their use. Be aware of alternatives and the PROs / CONs of the tool.
• Proficiency in using Excel/SQL/Python/Pandas/Analytics Workbench to process, transform, create variables and build models. Be or be working towards expert knowledge in a selection of these tools / approaches.

Building Models: Model building and validation, sales effects calculations, ROIs, media optimisation

• Oversee the building of comprehensive base models according to the project specification, incorporating all drivers of KPIs, providing rationale for variables entered, understanding coefficients and SFX.
• Taking base models, oversee or build in additional improvements and progress the model towards finalization.
• Calculate sales effects throughout the project to check results and assess their correctness, i.e. does media contribution make sense? Report to project team on preliminary findings and observations
• Create sales effect/ ROI workbook, ensure it is easy to follow and all links are correct.
• Create response curves and optimisation spreadsheets or alternatively use available tools for budget allocation. Run scenarios required to answer client objectives.
• Validate models, identify areas of weakness, suggest and test possible improvements and ensure robustness and validity.

.Creation of presentations: Content creation, summary of findings, accuracy checks

• Create content as specified by project lead, taking responsibility for entire sections rather than focusing on just factual and data slides.
• Assist in the creation of all areas of the deck as directed.
• Ensure that all content is checked for accuracy and that it is correctly labelled, complete and ready for delivery to client.
• Summarise and comment on findings, add consultancy input rather than on factual statements.
• Be able to explain and justify any potential changes that need to be made to provide sensible results. Especially important when reviewing others’ outputs that you are overseeing.

 Client Relationship Management & Interaction: Client contact and interaction, delivery of results to the client

• Answer specific data questions that may arise in external meetings as the lead analyst; act as a specialist closest to the data.
• Be prepared to lead calls with clients (data calls, weekly calls etc.).
• Be involved in the delivery of results to the client and present sections of presentations during meetings.
• Take charge of day-to-day client contact using email and telephone where appropriate.

 Interpretation of results: Result interpretation and rationale, recommendations, translation of results from analytics into actionable recommendations

• Provide input into the results and implications and comment on the interpretation for future strategies.
• Interpret results and understand the implications of these results to the client. Be able to explain your interpretation to the team and defend your POV.
• Be able to explain and justify any potential changes that need to be made to provide sensible results. Especially important when reviewing others’ outputs that you are overseeing.

 Team Support & Development: Team collaboration, leadership, communication

• Motivate and inspire team members by ensuring that excellent performance is acknowledged and reasons for success are shared amongst the team.
• Take responsibility for supervising, supporting and training junior team members.
• Take responsibility for training new joiners including project managing Graduate Analysts during their training project.
• Lead by behaving in a way that reinforces values and goals of Gain Theory to all employees.
• Assist team members in interpreting the tasks they have been set.
• Provide timely feedback to team members.

Innovation: Process improvements, product development, new trainings

• Actively seek more efficient ways of doing things for yourself and others and turn suggestions into actions.
• Host knowledge shares to share your experience on topics of interest for the business.
• Be proactive in using new tools and take the active part in their testing when in the development stage, in line with your personal expertise and skills.
• Assist in service and product development, where necessary. Actively put yourself forward if your involvement can improve outcomes for the company.

What we want from you:

• 2-3 years of experience in an analytical role, preferably within marketing analytics, consulting, or a related field.
• Deep understanding of analytical and modeling methodologies, including MMM, attribution, econometrics, and other advanced techniques.
• You can work within an inclusive and diverse team to deliver fresh thinking and innovative solutions. 
• You interact with colleagues and with our clients in a way that strengthens our culture of inclusivity, diversity, care, growth and recognition.
• You are tenacious, hardworking, curious and have a strong ability to communicate.
• You demonstrate a positive desire and strong aptitude for making data informed decisions.
• You can demonstrate good problem-solving skills and understanding of consumer behaviour.
• You have the capacity to work and learn quickly in a fast-paced environment.
• You take keen interest in your own learning and development.
• You demonstrate behaviours which support our values.
• Strong strategic thinking and problem-solving skills.
• Excellent communication, presentation, and stakeholder management skills.
• Proven project management experience, with the ability to manage multiple projects simultaneously.
• Proficiency in statistical software packages (e.g., R, Python) and data visualization tools.
• Bachelor's or Master's degree in a quantitative field (e.g., Statistics, Economics, Mathematics).

Why work for us? 

Gain Theory is committed to actively building a diverse, equitable and inclusive workplace where everyone feels welcomed, valued and heard, and is treated with dignity and respect.  As leaders and creative partners across industries, it is our responsibility to cultivate an environment reflective of our greatest asset; our people. We believe that this commitment inspires growth and delivers equitable outcomes for everyone as well as the clients and communities we serve. 

What we pride ourselves on: 

• Growth and development
• Meaningful work
• Flexible by design
• Brilliant benefits 
• Culture with Heart 
  
  

Our exceptional and skilled team defines Gain Theory. That's why we seek individuals who strive for excellence and continually challenge us to improve.

What we do 

Gain Theory is a global marketing effectiveness and foresight consultancy. Our vision is to accelerate growth for ambitious brands by giving clients the confidence to make better data-informed investment decisions. High-touch consultancy powered by unique partnerships and proprietary technology are used to power our award-winning solutions.  

 As a WPP consultancy, Gain Theory also has access to a range of data, expertise, and tools that create a truly differentiated offering. 

 Gain Theory is a WPP agency (NYSE: WPP).      

 Who we are 

We are a people-centric organisation whose culture is underpinned by 4 important values: Be Curious, Be Positive, Make it Better and Act with Consideration. We channel these values through our behaviours, in the way we work, and in the interactions we have with each other and our clients. 

The opportunity:

We are seeking a Senior Client Success Director with deep expertise in Marketing effectiveness and econometrics to lead our most strategic client relationships and shape the future of our client success function. In this senior leadership role, you will serve as a trusted advisor to C-suite executives, ensuring our advanced analytics solutions deliver measurable business outcomes while driving account growth and retention.

The Client Success Senior Director will be responsible for client leadership across a selection of Gain Theory’s portfolio. The ideal candidate should have a minimum of 8 years of experience in client relationship management and data analytics.

We expect this person to be the primary point of contact for senior client stakeholders and to act as a trusted advisor, deeply understanding client business objectives and leveraging Gain Theory’s expertise to deliver exceptional value and drive measurable results.

We require someone who has a deep understanding of data and analytics, is able to interpret complex datasets and extract actionable insights that drive client success.

This person should serve as an inspirational leader within the Client Success team, fostering a collaborative and results-oriented environment.

What you’ll be doing:

Project Delivery: 

• Ensures projects within remit are managed to time and scope. Highlights any risks to client lead.
• Puts in place robust quality assurance techniques and follows them to ensure work going to clients is right first time.
• Uses data and analytics interpretation skills to bring insights to life for a mid-senior audience (i.e. most senior day-to-day client stakeholder)
• Is a strong data storyteller who can explain complex insights at a simple, impactful level to a variety of audiences.
• Ensures clients have full knowledge and training of Gain Theory Interactive, highlighting any bugs or enhancements to the GTI team.
• Ensures projects are following Operational Excellence process and that there is full adherence from Client Success team.

Financial: 

• ​Looks for opportunities to drive profitable growth for clients and take on incremental (e.g. 1-30% growth) opportunities. Bring in client lead and senior team for larger opportunities.
• Identifies values driven for clients and looks to assist clients in recognising that value.
• Understands how decisions made on projects will impact profitability and looks to run more efficient processes or tighter management of scope, designed in consultancy with client lead.
• Understands how actions they take will impact overall Gain Theory profitability and looks to make the right decisions towards this at all times
• Is involved in new business pitches as part of a wider team. May be expected to lead opportunities that do not need a large team.

Client Management: 

• Manages against SOW to ensure limited scope creep and slippages.
• Implements plans to drive higher client satisfaction across every metric, highlighting any issues to client leadership.
• Helps to increase the number of stakeholders and advocacy at the right level (e.g. most senior day to day stakeholder). Works with client leadership to embed plan.
• Works with client leadership on risk mitigation process, highlighting any risks early and working on plans to mitigate.

Thought Leadership: 

• Has sufficient knowledge of most of Gain Theory solutions, systems and ways of working to have a healthy conversation with a client in any aspect of Gain Theory's offering. Is actively looking to learn in this space.
• Maintains a solid understanding of their clients' industries, keeping up to date with key trends and seeking opportunities for growth.
• Maintains a good understanding of the marketing effectiveness industry, assessing for threats, challenges and opportunities that said industry presents to client relationships.

Values & Team: 

• Is an inspirational leader for Client Success Managers.
• Implements initiatives to improve Client Success team satisfaction within squad. Understands what drives employee satisfaction and looks to make things better for all.
• Facilitates collaborative learning and knowledge sharing to boost team capabilities.

KPIs & Success Factors: 

• Net Sales Growth
• # of Client Stakeholders
• Client Influence
• Client Advocacy
• Client Satisfaction
• Client Success Practice Area ESAT
• OPEX Implementation
• Value generated for Clients
• Awards entered

What we want from you:

• 8+ years of experience in client success, consulting, or marketing analytics roles, with significant client-facing responsibility.
• Demonstrated expertise in Marketing Mix Modeling and econometrics (model interpretation, ROI analysis, elasticity, attribution methods).
• Proven ability to lead, manage, and develop high-performing Client Success teams.
• Demonstrated success in managing enterprise portfolios and influencing C-suite stakeholders across global brands.
• Demonstrated ability to manage client relationships and communicate complex analytics to non-technical audiences.
• Strong strategic thinking and problem-solving skills.
• Strong commercial mindset with experience identifying new opportunities.
• Excellent communication, presentation, and stakeholder management skills.
• Proven project management experience, with the ability to manage multiple projects simultaneously.
• Skilled in tools such as Excel, PowerPoint, and at least one analytics environment (R, Python, or similar).
• Bachelor's or Master's degree in a quantitative field (e.g., Statistics, Economics, Mathematics).

Why work for us? 

Gain Theory is committed to actively building a diverse, equitable and inclusive workplace where everyone feels welcomed, valued and heard, and is treated with dignity and respect.  As leaders and creative partners across industries, it is our responsibility to cultivate an environment reflective of our greatest asset; our people. We believe that this commitment inspires growth and delivers equitable outcomes for everyone as well as the clients and communities we serve. 

What we pride ourselves on: 

• Growth and development
• Meaningful work
• Flexible by design
• Brilliant benefits 
• Culture with Heart 
  
  

Our exceptional and skilled team defines Gain Theory. That's why we seek individuals who strive for excellence and continually challenge us to improve.

What we do 

Gain Theory is a global marketing effectiveness and foresight consultancy. Our vision is to accelerate growth for ambitious brands by giving clients the confidence to make better data-informed investment decisions. High-touch consultancy powered by unique partnerships and proprietary technology are used to power our award-winning solutions.  

 As a WPP consultancy, Gain Theory also has access to a range of data, expertise, and tools that create a truly differentiated offering. 

 Gain Theory is a WPP agency (NYSE: WPP).      

 Who we are 

We are a people-centric organisation whose culture is underpinned by 4 important values: Be Curious, Be Positive, Make it Better and Act with Consideration. We channel these values through our behaviours, in the way we work, and in the interactions we have with each other and our clients.