Senior UX/UI Designer (CRO)

📍 Job Overview

Job Title: Senior UX/UI Designer (CRO)

Company: VML/WPP Enterprise Solutions

Location: London, England, United Kingdom

Job Type: Full-time

Category: UX/UI Design, Conversion Rate Optimization (CRO)

Date Posted: September 16, 2026

Experience Level: Mid-Senior Level (implied by "Senior" title and 5-10 years AI-estimated experience)

Remote Status: Hybrid

🚀 Role Summary

• Lead the end-to-end UX/UI design process for A/B and multivariate testing initiatives, focusing on optimizing digital experiences across web and mobile platforms.

• Translate complex user data, behavioral analytics, and strategic hypotheses into high-impact design variations and optimized user journeys to drive conversion.

• Collaborate intensely within a cross-functional CRO squad, working closely with strategists, analysts, product managers, and developers to manage experimentation pipelines.

• Design, optimize, and deliver premium web experiences and landing pages that maximize user engagement, conversion rates, and support overall business growth objectives.

📝 Enhancement Note: This role is specifically for a designer deeply embedded within a Conversion Rate Optimization (CRO) squad. The emphasis is on data-driven design, rapid iteration through experimentation (A/B, multivariate testing), and a strong understanding of user psychology and persuasive design principles to achieve measurable business outcomes, particularly in digital commerce and lead generation contexts.

📈 Primary Responsibilities

• Lead the end-to-end UX/UI design lifecycle for A/B testing, multivariate testing, landing pages, and ongoing optimization initiatives across web and mobile platforms.

• Develop detailed user flows, interaction models, wireframes, and interactive, high-fidelity prototypes specifically optimized for experimentation and user validation.

• Create pixel-perfect UI designs that adhere to and elevate client brand guidelines, employing persuasive design patterns, psychological triggers, and clear, conversion-focused hierarchies.

• Design and optimize unique, tailored user journeys for a portfolio of client sub-brands, balancing sub-brand visual identities with core design system architectures.

• Focus on landing page layouts, micro-interactions, persuasive copywriting placement, and checkout/signup funnel optimization to systematically minimize user friction.

• Translate user feedback, testing data, and statistical results from A/B tests into actionable, iterative design recommendations.

• Ensure technical feasibility of experiment designs, collaborating closely with developers for implementation and reviewing builds for high-fidelity execution.

• Work closely with CRO Strategists, Web Analysts, Product Managers, and front-end Developers in a fast-paced, agile squad environment.

• Advocate for data-informed, evidence-based design decisions, presenting design concepts and experimentation rationale clearly to clients and stakeholders.

• Contribute to and maintain conversion-oriented design libraries, templates, and documented best practices to scale optimization efforts.

📝 Enhancement Note: The responsibilities highlight a hands-on role requiring end-to-end ownership of design within an experimentation framework. The emphasis on "pixel-perfect UI designs," "persuasive design patterns," and "conversion-focused hierarchies" underscores the critical link between design execution and measurable conversion uplift. The requirement to work with "tokenized design systems" and "multi-brand navigation" points to a complex client environment requiring scalable and adaptable design solutions.

🎓 Skills & Qualifications

Education: While no specific degree is mentioned, a Bachelor's or Master's degree in Graphic Design, Interaction Design, Human-Computer Interaction, or a related field is typically expected for senior-level roles. Equivalent practical experience will also be considered.

Experience: 5-10 years of experience in UX/UI design, with a significant focus on conversion rate optimization (CRO), A/B testing, or landing page optimization. Experience working within agile, cross-functional teams is essential.

Required Skills:

• Tokenized Design Systems (DS) Mastery: Deep understanding and practical experience working with and leveraging tokenized design systems (e.g., design tokens in Figma) for styling variables, thematic brand changes, and cross-platform consistency.

• Figma & Prototyping Proficiency: Exceptional proficiency in Figma, including the ability to create structured, scalable design files, component libraries, and realistic prototypes for testing.

• Conversion-Centered Design Principles: Deep understanding of user psychology, persuasive design, usability standards, and conversion-focused user journey optimization.

• Multi-Brand Design Experience: Proven ability to design distinct user journeys and interfaces for multiple sub-brands while maintaining core systemic rules and brand consistency.

• Technical Understanding: Solid grasp of front-end capabilities (HTML, CSS, and basic JavaScript limitations) to ensure designs are technically feasible and performant.

• Web Accessibility (WCAG) & Performance: Strong understanding of accessibility standards and page performance considerations for inclusive and fast user experiences.

• Agile Collaboration & Communication: Strong communication skills, comfortable presenting design rationale to stakeholders, and adept at working in fast-paced agile development/testing cycles.

Preferred Skills:

• Experience designing for A/B testing, personalization, CRO, or landing page optimization, with demonstrable examples of design decisions informed by user insight, performance data, or test learnings.

• Experience designing high-converting experiences for e-commerce, transactional websites, lead-generation pages, or digital products.

📝 Enhancement Note: The emphasis on "Tokenized Design Systems" and "Multi-Brand Navigation" suggests the company works with clients who have complex brand portfolios and require scalable design solutions. The requirement for a strong portfolio is paramount, specifically highlighting how data and experimentation inform design outcomes. Technical understanding of front-end capabilities is crucial for ensuring designs are implementable and performant within testing frameworks.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• A strong portfolio is a mandatory requirement, showcasing a clear end-to-end design process.

• Demonstrate how user insights, performance data, or test hypotheses were used to design landing pages, optimized user flows, and successful A/B test variations.

• Include case studies that highlight specific CRO initiatives, detailing the problem, your design approach, the experimentation conducted, and the measurable results (e.g., conversion uplift, reduced friction).

• Showcase examples of working with and adapting designs within a design system, ideally demonstrating experience with tokenized systems.

• Highlight experience in designing for multi-brand environments and tailoring experiences for different sub-brands. Process Documentation:

• Experimentation Design Process: Detail your approach to designing for A/B and multivariate tests, from hypothesis generation to final design specifications.

• User Research & Data Analysis Integration: Illustrate how you incorporate user feedback, behavioral analytics, and A/B test results into your design iterations.

• Design System Utilization & Contribution: Showcase how you leverage existing design systems and potentially contribute to their evolution, particularly with regard to design tokens.

• Cross-Functional Collaboration Workflows: Describe your process for collaborating with CRO Strategists, Analysts, Developers, and Product Managers within an agile squad.

📝 Enhancement Note: The portfolio is critical and must specifically showcase conversion-focused design work and the ability to iterate based on experimental data. The emphasis on "measurable results" and "successful A/B test variations" means candidates should prepare to articulate the impact of their designs quantitatively. Experience with design systems, especially tokenized ones, is a key differentiator.

💵 Compensation & Benefits

Salary Range: Based on London, England, United Kingdom location, "Senior UX/UI Designer" title, and the hybrid work arrangement, a competitive salary range is estimated to be between £60,000 - £85,000 per annum. This estimate considers the specialized CRO focus, the need for deep design system expertise, and the agency environment within WPP Enterprise Solutions, which often involves client-facing work.

Benefits:

• Discretionary bonus scheme

• Training opportunities for professional development

• Competitive pension scheme

• Comprehensive medical insurance

• Life assurance

• Regular social events

• Opportunities to buy and sell holidays

• Family-friendly policies

• Discounts with hundreds of retailers

Working Hours: Standard full-time working hours are assumed to be around 40 hours per week, with flexibility often offered in a hybrid environment.

📝 Enhancement Note: The salary estimate is based on current market data for senior UX/UI designers in London, with an uplift for the specialized CRO and design system expertise required. The benefits package is comprehensive and typical for a large, established organization like WPP. The AI-estimated 40 working hours per week is a standard benchmark.

🎯 Team & Company Context

🏢 Company Culture

Industry: Marketing and Advertising, Enterprise Solutions, Digital Transformation, Consulting. WPP Enterprise Solutions focuses on building growth systems for businesses, leveraging technology, data, and platforms. VML, part of WPP, brings creativity and experience design to these transformations.

Company Size: Part of WPP, which is a global leader with 12,000+ experts globally. VML/WPP Enterprise Solutions likely operates as a significant unit within this structure, indicating a large, well-resourced organization with diverse capabilities.

Founded: WPP was founded in 1982. VML was founded in 1997 and merged with Wunderman in 2020 to form Wunderman Thompson, which then merged with Y&R and VML to form VML in 2024. This history suggests a company with deep roots in advertising and a continuous evolution towards integrated digital solutions.

Team Structure:

• The role is embedded within a dedicated CRO squad, indicating a cross-functional team structure focused on experimentation and optimization.

• This squad likely includes roles such as CRO Strategists, Web Analysts, Product Managers, and Front-end Developers, working collaboratively.

• The Senior UX/UI Designer will report into a design lead or potentially the CRO squad lead, with close collaboration across various client teams and internal WPP Enterprise Solutions departments. Methodology:

• Agile Squads: The team operates within agile squad environments, emphasizing iterative development, rapid feedback, and continuous improvement.

• Data-Informed Decision Making: A core methodology is using user data, behavioral analytics, and A/B test results to inform design and strategy.

• Growth Systems Focus: The overarching approach is to design, build, and operate "growth systems" that connect strategy directly to execution for clients.

• Partnership Integration: Close collaboration with technology partners (Adobe, AWS, Google, Microsoft, Salesforce, etc.) is fundamental.

Company Website: https://www.vml.com/ and https://www.wpp.com/

📝 Enhancement Note: The company context highlights a global agency network focused on driving client growth through sophisticated digital solutions. The "CRO squad" structure emphasizes a specialized, agile, and data-driven approach to design and optimization, requiring designers to be highly collaborative and performance-oriented. The "growth systems" concept implies a strategic, holistic view of client operations.

📈 Career & Growth Analysis

Operations Career Level: This is a "Senior" role, indicating a position of significant responsibility, autonomy, and expertise. The designer is expected to lead design efforts for complex experimentation projects, mentor junior designers (potentially), and influence design strategy within the CRO squad and for clients. This level typically requires a strong portfolio and a proven track record of delivering impactful results.

Reporting Structure: The Senior UX/UI Designer will be embedded within a dedicated CRO squad, likely reporting to a CRO Lead, Design Manager, or Head of Experience within VML/WPP Enterprise Solutions. They will collaborate extensively with CRO Strategists, Web Analysts, Product Managers, and Front-end Developers.

Operations Impact: The impact of this role is directly tied to driving measurable business outcomes for clients. By designing and optimizing user experiences through experimentation, the designer directly contributes to increased conversion rates, improved user engagement, reduced friction in critical funnels (e.g., checkout, sign-up), and ultimately, enhanced revenue and business growth for clients. This is a highly analytical and results-oriented design role, far removed from purely aesthetic contributions.

Growth Opportunities:

• Specialization in CRO & Experimentation: Deepen expertise in conversion-focused design, advanced A/B testing methodologies, and user psychology.

• Design Leadership: Progress into roles leading design for larger CRO programs, managing multiple squads, or mentoring junior design talent.

• Client Strategy Influence: Become a key advisor to clients on UX and optimization strategy, shaping their digital growth initiatives.

• Design System Evolution: Contribute to the development and governance of advanced, tokenized design systems for large-scale client portfolios.

• Cross-Disciplinary Learning: Gain deeper insights into analytics, product management, and business strategy through close collaboration.

📝 Enhancement Note: This role offers a clear path for growth within a specialized, high-impact area of design. The emphasis on data and measurable results positions the designer as a strategic partner rather than a service provider, offering significant career advancement potential in a high-demand field.

🌐 Work Environment

Office Type: The job is listed as Hybrid, suggesting a mix of remote work and in-office collaboration. VML/WPP Enterprise Solutions likely has modern office spaces designed to facilitate collaboration, client meetings, and team working sessions.

Office Location(s): The primary location is London, England, United Kingdom. WPP is a global company with numerous offices, so while this role is based in London, there might be opportunities for interaction with global teams.

Workspace Context:

• Collaborative Environment: The role requires close collaboration within a dedicated CRO squad, suggesting an open and interactive workspace conducive to brainstorming and rapid iteration.

• Tools & Technology: Access to industry-standard design tools (Figma), prototyping software, and potentially client-specific analytics platforms will be available.

• Client-Facing Interaction: As part of an enterprise solutions provider, there will be opportunities to engage with client stakeholders, requiring a professional and adaptable working style.

• Agile Workflow: The environment supports fast-paced agile workflows, demanding flexibility and efficient task management.

Work Schedule: A hybrid work schedule is expected, allowing for remote work days combined with in-office days for team collaboration and client engagement. Standard business hours are likely, with a focus on task completion and project delivery.

📝 Enhancement Note: The hybrid nature of the role offers flexibility, while the embedded squad structure emphasizes close-knit team collaboration. The workspace will be geared towards supporting analytical design work and agile project management.

📄 Application & Portfolio Review Process

Interview Process:

• Initial Screening: A recruiter or hiring manager will review applications, focusing on CVs and portfolios for relevant experience, particularly in CRO, A/B testing, and design systems.

• Portfolio Review & Presentation: Candidates will likely be asked to present their portfolio, with a specific focus on case studies demonstrating their CRO design process, data-informed decision-making, and measurable results. Be prepared to discuss the "why" behind your design choices and the impact of your work.

• Skills-Based Interview / Technical Assessment: This may involve a design challenge or a discussion of specific design systems, Figma proficiency, and front-end technical understanding. A practical exercise related to optimizing a landing page or user flow for conversion might be included.

• Squad/Team Interview: Meetings with potential team members (CRO Strategists, Developers, Product Managers) to assess collaboration style, cultural fit, and ability to work within an agile, data-driven environment.

• Final Interview: A discussion with senior leadership to assess strategic thinking, client-facing capabilities, and overall fit with VML/WPP Enterprise Solutions' values and mission.

Portfolio Review Tips:

• Curate for CRO: Select 3-5 strong case studies that specifically highlight your experience in Conversion Rate Optimization, A/B testing, landing page design, and user journey optimization.

• Structure for Impact: For each case study, clearly articulate: the client/project, the problem/hypothesis, your role and process, the design solutions, the testing methodology, and the quantifiable results (e.g., conversion rate increase, revenue impact, engagement metrics). Use visuals effectively.

• Highlight Data & Insights: Emphasize how user data, analytics, and test learnings informed your design decisions. Show your analytical thinking alongside your creative skills.

• Demonstrate Design System Proficiency: Include examples of how you've worked with design systems, ideally showcasing experience with design tokens and multi-brand applications.

• Be Ready to Discuss: Prepare to verbally walk through your process, justify your design choices, and discuss challenges and learnings from each project.

Challenge Preparation:

• Optimization Scenarios: Practice analyzing a given landing page or user flow and proposing specific design improvements to increase conversion rates. Consider common CRO tactics and psychological principles.

• Design System Application: Be ready to discuss how you would adapt a design system for a new brand or implement changes using design tokens.

• Collaboration Simulation: Prepare to discuss how you would collaborate with a CRO strategist to define test hypotheses or with a developer to ensure accurate implementation of a complex test variation.

📝 Enhancement Note: The interview process heavily emphasizes practical application of CRO principles and the ability to demonstrate measurable impact through a portfolio. Candidates should prepare to articulate their process, rationale, and results with a data-driven mindset. Understanding of design systems and agile methodologies is key.

🛠 Tools & Technology Stack

Primary Tools:

• Figma: Essential for UI design, wireframing, prototyping, and component/design system management. Mastery is expected.

• Prototyping Tools: Figma's built-in prototyping capabilities are key, but experience with others like InVision or Axure might be beneficial.

• Design Systems Management: Familiarity with tools or methodologies for managing design tokens and component libraries within Figma.

Analytics & Reporting:

• Web Analytics Platforms: Experience with tools like Google Analytics, Adobe Analytics, or similar platforms to understand user behavior and analyze test results.

• A/B Testing Platforms: Familiarity with platforms such as Optimizely, Adobe Target, Google Optimize (though sunsetting), VWO, or similar experimentation tools.

• Data Visualization Tools: Potentially experience with tools like Tableau, Power BI, or custom dashboards for interpreting performance data.

CRM & Automation:

• While not directly a CRM design role, understanding how design impacts CRM-related funnels (e.g., lead capture forms) and marketing automation flows is beneficial. Familiarity with platforms like Salesforce, HubSpot, or Braze may be advantageous in understanding client contexts.

• Project Management Tools: Tools like Jira, Asana, Trello for managing tasks within agile squads.

📝 Enhancement Note: Proficiency in Figma and a strong understanding of A/B testing platforms are non-negotiable. The ability to interpret data from analytics tools to inform design decisions is crucial. Experience with design systems, particularly tokenized ones, is a significant advantage.

👥 Team Culture & Values

Operations Values:

• Impact-Driven: A strong focus on delivering measurable results and driving tangible growth for clients. Design decisions are validated by data and performance metrics.

• Curiosity & Continuous Learning: Valuing relentless curiosity to solve complex challenges and staying updated on design trends, CRO best practices, and new technologies.

• Collaboration & Empathy: Fostering empathy and trust within teams, leading to genuine connections and human-centric work. Working collaboratively across disciplines is essential.

• Courage & Experimentation: Encouraging individuals to speak up, embrace experimentation, and advocate for bold solutions that push boundaries and improve outcomes.

• Efficiency & Scalability: A drive for efficient processes and scalable solutions, particularly through the use of design systems and well-documented best practices.

Collaboration Style:

• Cross-Functional Integration: Seamless integration within agile CRO squads, working hand-in-hand with strategists, analysts, product managers, and developers.

• Data-Informed Dialogue: Engaging in constructive debates and discussions grounded in data and user insights to arrive at the best design solutions.

• Feedback Culture: Openness to giving and receiving constructive feedback on designs and processes to foster continuous improvement.

• Shared Ownership: A sense of shared ownership for the success of experiments and the overall growth objectives of the client.

📝 Enhancement Note: The company culture emphasizes a blend of analytical rigor, creative problem-solving, and collaborative teamwork. Success in this role hinges on being comfortable with data, embracing experimentation, and working effectively within a multidisciplinary team to achieve client business goals.

⚡ Challenges & Growth Opportunities

Challenges:

• Balancing Brand Identity with Optimization Goals: Designing for multiple client sub-brands while adhering to core design systems and driving universal conversion optimization can be complex.

• Translating Data into Actionable Design: Effectively interpreting diverse data sets (analytics, user feedback, test results) to inform specific, impactful design iterations.

• Rapid Iteration Cycles: Working within fast-paced agile environments that demand quick turnaround times for design variations and test implementations.

• Technical Constraints: Ensuring creative designs are technically feasible within client platforms and front-end limitations, especially within an experimentation context.

• Client Stakeholder Management: Effectively communicating design rationale and experimental outcomes to diverse client stakeholders with varying levels of technical and design understanding.

Learning & Development Opportunities:

• Advanced CRO Techniques: Deepen knowledge in areas like personalization, user journey mapping, and advanced experimentation strategies.

• Design System Expertise: Become a subject matter expert in tokenized design systems, their implementation, and scalability across large client portfolios.

• Cross-Disciplinary Skill Building: Gain deeper insights into web analytics, product strategy, and client business objectives through close team collaboration.

• Industry Conferences & Training: Access to professional development resources, conferences, and training relevant to UX, CRO, and design systems.

• Mentorship: Opportunities to learn from senior designers and CRO strategists, and potentially mentor junior team members.

📝 Enhancement Note: This role presents challenges that are also significant growth opportunities. Overcoming the complexity of multi-brand optimization and data-driven iteration will build a highly valuable and specialized skill set in the digital growth and optimization space.

💡 Interview Preparation

Strategy Questions:

• "Describe a time you used A/B testing data to significantly improve a user experience or conversion rate. What was your process, and what were the results?" (Focus on your role in hypothesis generation, design iteration, and impact.)

• "How do you approach designing for multiple sub-brands within a unified design system framework? Can you give an example of how you've managed brand distinctiveness while maintaining system consistency, potentially using design tokens?" (Highlight your understanding of design systems and multi-brand strategy.)

• "Walk us through your process for designing a landing page optimized for conversion. What key elements do you focus on, and how do you ensure it aligns with client goals?" (Demonstrate your conversion-centered design thinking.)

• "How do you collaborate with CRO strategists and developers to ensure your experimental designs are both effective and technically feasible?" (Showcase your teamwork and technical awareness.) Company & Culture Questions:

• "What interests you about VML/WPP Enterprise Solutions and our focus on growth systems?" (Research their client work, values, and approach to digital transformation.)

• "How do you embody our values of Heart, Brains, and Courage in your design work?" (Consider how you approach empathy, problem-solving, and advocating for bold ideas.)

• "Describe your ideal team environment. How do you contribute to a positive and productive cross-functional team dynamic?" (Align your collaboration style with their agile squad model.) Portfolio Presentation Strategy:

• Tell a Story: For each case study, frame it as a narrative: the challenge, your journey, the solution, and the outcome.

• Quantify Impact: Always lead with or prominently feature the measurable results. Use clear metrics and explain the business significance.

• Showcase Your Process: Explain your thinking at each stage – from research and ideation to iteration and final execution.

• Highlight CRO Specifics: Emphasize how data, user insights, and experimentation directly influenced your design decisions and led to optimization.

• Design System Integration: Clearly articulate your role in using or adapting design systems, especially if you have experience with design tokens.

• Be Prepared for Deep Dives: Expect questions about specific design choices, alternative solutions you considered, and how you handled technical or client feedback.

📝 Enhancement Note: Interview preparation should focus on articulating your CRO expertise, design system knowledge, and ability to drive measurable results. Be ready to showcase specific examples that align with the role's requirements, particularly around data-informed design and multi-brand application within a design system.

📌 Application Steps

To apply for this Senior UX/UI Designer (CRO) position:

• Submit your application through the provided link on Greenhouse.

• Tailor Your Resume: Optimize your resume to highlight keywords from the job description, such as "Conversion Rate Optimisation," "A/B Testing," "Figma," "Design Systems," "Tokenized Design Systems," "User Flows," "Prototyping," and "Data-driven Design." Quantify achievements wherever possible.

• Curate Your Portfolio: Select 3-5 strong case studies that specifically showcase your experience in CRO, A/B testing, and design system application. Ensure each case study clearly outlines the problem, your process, the design solution, and the measurable results. Make sure your portfolio link is prominent and easily accessible.

• Prepare for the Portfolio Presentation: Practice walking through your case studies, focusing on your data-informed design process, the impact of your work, and your ability to collaborate within a cross-functional team.

• Research VML/WPP Enterprise Solutions: Familiarize yourself with their company values (Heart, Brains, Courage), client work, and approach to digital transformation and growth systems. Understand how your skills align with their mission.

⚠️ Important Notice: This enhanced job description includes AI-generated insights and operations industry-standard assumptions. All details should be verified directly with the hiring organization before making application decisions.