Senior UX/UI Designer (CRO)

📍 Job Overview

Job Title: Senior UX/UI Designer (CRO)

Company: VML

Location: London, England, United Kingdom

Job Type: Full-Time

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

Date Posted: June 15, 2026

Experience Level: Mid-Senior Level (Estimated 5-10 years)

Remote Status: Hybrid (4 days in office)

🚀 Role Summary

• This role is central to driving measurable business growth through expert UX/UI design, with a specialized focus on Conversion Rate Optimization (CRO) and experimentation.

• You will be a hands-on designer embedded within a dedicated CRO squad, responsible for the end-to-end design lifecycle of A/B and multivariate tests.

• The position requires a deep understanding of user psychology, persuasive design, and data-informed decision-making to create high-performing digital experiences across web and mobile.

• You will leverage tokenized design systems to ensure brand consistency and scalability across multiple client sub-brands within a dynamic, agile environment.

📝 Enhancement Note: The job title "Senior UX/UI Designer (CRO)" and the description clearly indicate a specialization within UX/UI design focused on conversion optimization. The emphasis on A/B testing, multivariate testing, and data-driven design points to a role that is deeply integrated with performance marketing and GTM strategies, making it relevant to operations professionals who analyze and optimize customer journeys. The estimated experience level of 5-10 years aligns with a senior designation in this specialized field.

📈 Primary Responsibilities

• Lead the end-to-end UX/UI design process for A/B testing, multivariate testing, landing page development, 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 enhance client brand guidelines, employing persuasive design patterns, psychological triggers, and clear, conversion-focused hierarchies.

• Utilize and support tokenized design systems (DS) to ensure scalability, efficiency, and consistency of components across a multi-brand environment, managing thematic brand changes.

• Design and optimize unique user journeys tailored for a portfolio of client sub-brands, ensuring distinct visual identities and experiences are maintained while adhering to core design system architectures.

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

• Translate user feedback, behavioral analytics, and statistical results from A/B tests into actionable, iterative design recommendations for continuous improvement.

• Ensure all experiment designs are technically feasible and collaborate closely with front-end developers during implementation, providing detailed specifications and reviewing builds to ensure high-fidelity execution of tests.

• Work collaboratively within a fast-paced, agile CRO squad, partnering with CRO Strategists, Web Analysts, Product Managers, and front-end Developers to manage multiple experimentation pipelines.

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

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

📝 Enhancement Note: The responsibilities are heavily weighted towards practical application in CRO, emphasizing the design lifecycle for experiments, collaboration within a squad, and direct impact on conversion metrics. This suggests a role that requires strong analytical thinking alongside design skills, aligning with operations' focus on process efficiency and measurable outcomes.

🎓 Skills & Qualifications

Education: While no specific degree is listed, a Bachelor's degree in Design, Human-Computer Interaction, Psychology, Marketing, or a related field is typically expected for senior roles in this domain. Equivalent practical experience will also be considered.

Experience: Estimated 5-10 years of professional experience in UX/UI design, with a significant portion focused on conversion-centered design, landing page optimization, and A/B testing. Experience within an agency setting or working with multiple brands is highly beneficial.

Required Skills:

• Tokenized Design Systems (DS) Mastery: Deep understanding and practical experience working with and leveraging tokenized design systems (design tokens in Figma) for efficient styling, thematic branding, 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 user testing and developer handoff.

• Mastery of UX & Conversion Principles: Deep understanding of user psychology, persuasive design techniques, usability standards, responsive layouts, and platform-specific UX/UI guidelines.

• Multi-Brand Design Navigation: Proven ability to design distinct and unique user journeys for a client's various sub-brands, balancing brand customization with core systemic rules.

• Collaboration & Agility: Strong communication skills, with a collaborative mindset, comfortable presenting design rationale to stakeholders and working effectively in fast-paced agile development and testing cycles.

• Technical Understanding: Solid understanding of front-end capabilities, including HTML, CSS, and basic JavaScript, to ensure optimization designs are technically feasible and performant.

• Web Accessibility (WCAG) & Performance: Strong understanding of web accessibility standards and page performance considerations to design fast, inclusive, and seamless experiences.

Preferred Skills:

• Experience designing for A/B testing, personalization, CRO, or landing page optimization, particularly where design decisions are informed by user insight, performance data, or test learnings.

• Digital Commerce & Product Context: Experience designing high-converting experiences for e-commerce, transactional websites, lead-generation pages, or digital products.

• Experience working within a dedicated CRO squad or cross-functional experimentation team.

• Familiarity with user behavior analytics tools (e.g., Google Analytics, Hotjar, Crazy Egg) and A/B testing platforms (e.g., Optimizely, VWO, Google Optimize).

📝 Enhancement Note: The emphasis on "Tokenized Design Systems" and "Multi-Brand Navigation" highlights a need for sophisticated design operations and system thinking, crucial for managing complex client portfolios. The technical understanding requirement points to the need for designers who can bridge the gap between design and development feasibility.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• A compelling portfolio showcasing a clear end-to-end design process, specifically highlighting how user insights, data, or test hypotheses were used to design landing pages, optimized user flows, and successful A/B test variations.

• Demonstrate experience in creating and leveraging tokenized design systems, including examples of how design tokens were used to manage brand variations or thematic changes across different sub-brands.

• Include case studies that illustrate the design and optimization of transactional or lead-generation funnels, detailing the friction points identified and the design solutions implemented.

• Showcase examples of pixel-perfect UI designs that adhere to brand guidelines while incorporating persuasive design patterns and conversion-focused hierarchies, with clear justification for design choices. Process Documentation:

• Evidence of creating detailed user flows, interaction models, wireframes, and interactive prototypes for experimentation, with clear links between the design artifacts and the testing hypotheses.

• Documentation of how user feedback, testing data, and statistical results from A/B tests were translated into actionable design recommendations and iterative improvements.

• Examples of technical specifications provided to developers for design implementation and how builds were reviewed to ensure high-fidelity execution of tests.

• Demonstrate contributions to or maintenance of conversion-oriented design libraries, templates, and documented best practices for optimization efforts.

📝 Enhancement Note: The portfolio requirements are highly specific to CRO and experimentation. Candidates must be able to visually and narratively demonstrate their ability to impact conversion rates through design, using data and systematic approaches. This aligns with operations' need for quantifiable results and documented processes.

💵 Compensation & Benefits

Salary Range: Based on industry benchmarks for a Senior UX/UI Designer with a CRO specialization in London, England, United Kingdom, the estimated salary range is £60,000 - £85,000 per annum. This estimate considers the senior level, specialized skills in CRO, and the high cost of living in London, as well as VML's position as a large, established agency within the WPP network.

Benefits:

• Discretionary Bonus Scheme: Potential for additional compensation based on individual and company performance.

• Training Opportunities: Access to professional development, workshops, and learning resources to enhance skills.

• Competitive Pension: A robust pension plan to support long-term financial security.

• Medical Insurance: Comprehensive health coverage for employees and potentially their families.

• Life Assurance: Financial protection for dependents in the event of death.

• Social Events: Opportunities for team building and networking outside of work.

• Holiday Buy and Sell Scheme: Flexibility to manage annual leave entitlement.

• Family Friendly Policies: Support for employees with family responsibilities.

• Retail Discounts: Access to discounts with numerous retailers, offering savings on everyday purchases.

Working Hours: Standard full-time hours, typically 40 hours per week. The role is hybrid, with an expectation of working approximately four days per week in the London office, allowing for one day of remote work.

📝 Enhancement Note: The salary estimate is based on leveraging publicly available compensation data for similar roles in London, factoring in the seniority and specialized CRO focus. The benefits package is comprehensive and typical for a large agency environment, offering strong support for employee well-being and professional growth.

🎯 Team & Company Context

🏢 Company Culture

Industry: Marketing & Advertising, Digital Transformation, Experience Design. VML operates within the broader WPP ecosystem, a global leader in marketing and communications services. This industry context means a focus on client success, creative excellence, and delivering measurable business impact.

Company Size: VML is part of WPP, a massive global entity with over 26,000 employees across 55+ markets. VML itself is a significant agency with principal offices worldwide, indicating a large, resource-rich organization with established processes and a broad client base.

Founded: VML was formed from the merger of Wunderman Thompson and VMLY&R in 2024, continuing a legacy of innovation and client service. The company's history is rooted in digital marketing and creative solutions, now combined to offer a more comprehensive suite of services.

Team Structure:

• The role is embedded within a dedicated CRO squad, a cross-functional team likely comprising CRO Strategists, Web Analysts, Product Managers, and Front-end Developers. This structure emphasizes agile, collaborative work focused on specific client objectives.

• The Senior UX/UI Designer (CRO) will report into a Design Lead or Head of Experience within the Enterprise Solutions division, with a matrix reporting line into the CRO squad lead for project-specific work.

• Expect close collaboration not only within the CRO squad but also with broader design, strategy, and client services teams across VML and WPP. Methodology:

• Data-Driven Design: Decisions are heavily influenced by user data, behavioral analytics, and the results of A/B and multivariate testing.

• Agile Experimentation: A rapid, iterative approach to testing design hypotheses, learning from results, and quickly implementing optimizations.

• Systematic Optimization: A continuous process of identifying opportunities, designing variations, testing, and refining to improve key performance indicators (KPIs) such as conversion rates, engagement, and revenue.

• Tokenized Design Systems: A systematic approach to managing design components and brand consistency across a large portfolio, enabling efficient deployment and maintenance.

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

📝 Enhancement Note: The company context highlights a large, integrated agency structure focused on driving client growth through digital transformation and creative solutions. The emphasis on "Enterprise Solutions" suggests a focus on large-scale, complex client challenges, and the CRO squad structure points to a highly collaborative and data-centric operational model.

📈 Career & Growth Analysis

Operations Career Level: This is a Senior-level individual contributor role. It signifies a high degree of autonomy, expertise, and the ability to lead design initiatives within the CRO domain. The role requires not just design execution but also strategic input into experimentation hypotheses and design rationale. It sits at a crucial intersection of design, analytics, and business objectives, making it a valuable position for those focused on optimizing customer journeys.

Reporting Structure: The designer will be part of a dedicated CRO squad, working closely with strategists, analysts, and developers. They will likely report to a Design Director or Head of UX/UI within VML's Enterprise Solutions division, with day-to-day guidance and project direction coming from the CRO squad lead. This structure allows for both specialized expertise and cross-functional team integration.

Operations Impact: The primary impact of this role is on driving measurable business growth for VML's clients through increased conversion rates, improved user engagement, and enhanced customer journey efficiency. By optimizing digital experiences, the designer directly contributes to client revenue and ROI, making them a critical component of the Go-To-Market (GTM) strategy for digital products and campaigns.

Growth Opportunities:

• Specialization Advancement: Deepen expertise in CRO, A/B testing, personalization, and behavioral economics, potentially leading to a specialization in complex experimentation or user journey optimization.

• Leadership Development: Progress into a Lead UX/UI Designer role, mentoring junior designers, managing design projects, or taking on a more strategic role within CRO squads or client accounts.

• Cross-Functional Skill Development: Gain deeper insights into web analytics, CRO strategy, product management, and front-end development, broadening skill sets for a more holistic understanding of digital product development and optimization.

• Client Strategy Involvement: Contribute to high-level client strategy discussions, influencing the direction of optimization efforts and the design of digital products.

📝 Enhancement Note: The growth opportunities are geared towards deepening specialization in CRO and expanding into leadership or strategic client-facing roles, reflecting the impact and value of this function within an agency.

🌐 Work Environment

Office Type: VML operates a hybrid work model, indicating a blend of in-office collaboration and remote flexibility. The London office is likely a modern, well-equipped space designed to foster collaboration, creativity, and client engagement.

Office Location(s): Based in London, England, United Kingdom. Specific office address details would typically be provided upon inquiry or during the interview process. The hybrid model implies easy access to public transportation and amenities common in a major metropolitan area.

Workspace Context:

• Collaborative Environment: The office space is designed to facilitate interaction, brainstorming, and co-creation among team members, essential for agile squad work and client presentations.

• Operations Tools & Technology: Access to industry-standard design software (Figma), prototyping tools, and potentially collaboration platforms (e.g., Slack, Microsoft Teams) and project management software.

• Team Interaction: Frequent opportunities for direct interaction with CRO strategists, analysts, developers, product managers, and other designers, fostering a dynamic and supportive work atmosphere.

Work Schedule: The role is full-time, with a standard 40-hour work week. The hybrid arrangement offers flexibility, with approximately four days per week expected in the office. This structure allows for focused individual work and collaborative team sessions, balancing efficiency with necessary in-person interaction.

📝 Enhancement Note: The hybrid nature of the role, with a significant in-office component (4 days/week), suggests an emphasis on in-person collaboration and team synergy, which is common for agencies that prioritize client-facing work and creative ideation.

📄 Application & Portfolio Review Process

Interview Process:

• Initial Screening: A review of your resume and portfolio by a recruiter to assess basic qualifications and alignment with the role's requirements.

• Design Challenge/Portfolio Review: A session where you will present your portfolio, focusing on case studies that demonstrate your CRO expertise, design process, data-informed decision-making, and ability to work with design systems. Be prepared to discuss specific projects, your role, the challenges, your solutions, and the outcomes.

• Hiring Manager/Squad Lead Interview: A deeper dive into your experience, design philosophy, collaboration style, and understanding of CRO principles. Expect questions about how you approach experimentation design and translate data into actionable insights.

• Cross-Functional Team Interview: An opportunity to meet with potential colleagues from the CRO squad (e.g., CRO Strategist, Web Analyst, Developer) to assess cultural fit, collaboration skills, and technical understanding.

• Final Interview: Potentially with a senior leader (e.g., Head of Design, Director) to discuss career aspirations and overall fit within VML's broader strategy.

Portfolio Review Tips:

• Curate for CRO: Select 3-5 projects that best showcase your experience in A/B testing, landing page optimization, user journey mapping, and conversion-focused design. Prioritize projects with quantifiable results.

• Structure Your Case Studies: For each project, clearly outline the problem, your role, the process (research, ideation, design, testing), the solutions, and the impact (metrics, learnings). Use visuals effectively.

• Highlight Design System Usage: Specifically demonstrate how you've utilized tokenized design systems, explaining how they enabled efficient multi-brand design or thematic changes.

• Explain Your Rationale: Be prepared to articulate why you made specific design decisions, linking them back to user data, psychological principles, or experimentation hypotheses.

• Showcase Technical Feasibility: Briefly explain how your designs considered front-end constraints and performance.

Challenge Preparation:

• Experimentation Mindset: Practice thinking about user behavior, identifying conversion bottlenecks, and formulating testable hypotheses.

• Design System Application: If given a scenario, think about how you would apply or adapt an existing design system, especially tokenized elements, to meet specific brand or campaign needs.

• Data Interpretation: Be ready to discuss how you would interpret common A/B test results and what design iterations might follow.

📝 Enhancement Note: The interview and portfolio review process is heavily focused on practical application of CRO principles and design system proficiency. Candidates need to demonstrate not just design skill but a strategic, data-driven approach to optimization.

🛠 Tools & Technology Stack

Primary Tools:

• Figma: The core tool for UX/UI design, wireframing, prototyping, and managing design systems. Proficiency in creating structured, component-based files and leveraging design tokens is essential.

• Prototyping Tools: Within Figma or standalone (e.g., InVision, Axure) for creating interactive prototypes to test user flows and validate design concepts.

• Design Systems: Experience working with and contributing to tokenized design systems (design tokens) for managing UI components, themes, and brand variations.

Analytics & Reporting:

• Web Analytics Platforms: Familiarity with tools like Google Analytics, Adobe Analytics, or similar to understand user behavior, track performance metrics, and identify optimization opportunities.

• User Behavior Tools: Experience with tools such as Hotjar, Crazy Egg, or FullStory for heatmaps, session recordings, and user feedback analysis.

• A/B Testing Platforms: Exposure to platforms like Optimizely, VWO (Visual Website Optimizer), Google Optimize, or Adobe Target for designing, implementing, and monitoring experiments.

CRM & Automation:

• While not a primary focus for a designer, an understanding of how design impacts lead generation and customer journeys within CRM systems (e.g., Salesforce) can be beneficial.

• Familiarity with marketing automation platforms (e.g., Marketo, HubSpot) might be useful for understanding the broader customer engagement lifecycle.

📝 Enhancement Note: The technology stack is heavily skewed towards design and experimentation tools. Proficiency in Figma and understanding how to leverage design systems are paramount. Familiarity with analytics and testing platforms is crucial for a CRO-focused role.

👥 Team Culture & Values

Operations Values:

• Heart (Empathy & Trust): Fostering genuine connections and human-centric work. This translates to understanding user needs deeply and building collaborative relationships within the team and with clients.

• Brains (Curiosity & Intelligence): Valuing relentless curiosity and collaborative intelligence to solve complex challenges. This means a data-driven, analytical approach to design and a willingness to explore new optimization strategies.

• Courage (Boldness & Advocacy): Inspiring individuals to speak up, embrace experimentation, and advocate for bold solutions. This encourages proactive design recommendations, challenging the status quo, and championing data-informed design decisions.

• Impact-Driven: A strong focus on delivering measurable business results for clients, with design decisions directly contributing to growth metrics.

• Data-Informed: Prioritizing evidence-based design, using analytics and testing results to guide and validate creative output.

Collaboration Style:

• Agile & Cross-Functional: Working within dedicated squads, emphasizing close collaboration with strategists, analysts, product managers, and developers to achieve shared goals rapidly.

• Transparent Communication: Openly sharing design rationale, test hypotheses, and results with stakeholders to build alignment and foster trust.

• Iterative & Feedback-Oriented: A culture of continuous improvement, where designs are tested, feedback is incorporated, and processes are refined based on learnings.

• Client-Centric: A strong focus on understanding and meeting client objectives, presenting work professionally, and building strong client relationships.

📝 Enhancement Note: The company's core values (Heart, Brains, Courage) are deeply integrated into how teams are expected to operate, particularly in a creative agency setting. For operations professionals, this translates to a data-driven, collaborative, and innovative approach to problem-solving and execution.

⚡ Challenges & Growth Opportunities

Challenges:

• Balancing Brand Consistency with Experimentation: Designing unique, high-converting variations for multiple sub-brands while maintaining core design system integrity and brand guidelines.

• Translating Complex Data into Design: Effectively interpreting user behavior analytics and A/B test results to generate insightful, actionable design hypotheses and solutions.

• Managing Multiple Experimentation Pipelines: Juggling design responsibilities for various tests and optimization initiatives simultaneously within a fast-paced, agile environment.

• Ensuring Technical Feasibility: Designing innovative solutions that are also technically achievable within development constraints and budget, requiring close collaboration with developers.

• Advocating for Data-Informed Design: Persuading stakeholders, including clients, to adopt design decisions based on data and test results, especially when they challenge existing assumptions.

Learning & Development Opportunities:

• Advanced CRO Specialization: Deepen expertise in areas like personalization, advanced testing methodologies, and user psychology for conversion optimization.

• Design System Leadership: Grow skills in managing, evolving, and advocating for design systems, potentially leading to system architecture or governance roles.

• Cross-Disciplinary Exposure: Gain hands-on experience with analytics platforms, CRO strategy development, and product management principles through close collaboration within the squad.

• Client Strategy & Presentation Skills: Develop stronger client-facing communication and strategic thinking capabilities, moving beyond execution to influence broader client roadmaps.

• Mentorship: Opportunities to mentor junior designers and learn from experienced leaders within VML's extensive network.

📝 Enhancement Note: The challenges highlight the nuanced nature of CRO design, requiring a blend of creativity, analytical rigor, and stakeholder management. The growth opportunities focus on deepening specialized skills and expanding influence within the agency and client landscape.

💡 Interview Preparation

Strategy Questions:

• "Describe a time you used user data or A/B test results to significantly improve a digital experience's conversion rate. What was your process, what were the challenges, and what was the outcome?" (Focus on demonstrating your CRO process and impact.)

• "How do you approach designing for multiple sub-brands within a single design system? Walk us through a specific example of how you've managed brand variation using design tokens." (Assess your understanding of design systems and multi-brand environments.)

• "Imagine a client's checkout funnel has a high drop-off rate. What steps would you take as a UX/UI designer to diagnose the issue and propose design-led solutions for A/B testing?" (Evaluate your problem-solving approach and CRO mindset.) Company & Culture Questions:

• "What interests you about VML and this specific CRO-focused role within our Enterprise Solutions division?" (Show your alignment with VML's mission and the role's specialization.)

• "How do you embody VML's core values of Heart, Brains, and Courage in your daily work and collaborations?" (Prepare examples that demonstrate empathy, analytical thinking, and proactive problem-solving.)

• "How do you ensure your designs are both user-centric and aligned with business objectives, particularly in a fast-paced agency environment?" (Highlight your ability to balance user needs with client goals and operational realities.) Portfolio Presentation Strategy:

• Select Targeted Projects: Choose 3-5 projects that clearly demonstrate your CRO expertise, design process, and ability to work with design systems. Prioritize those with measurable results.

• Tell a Story: For each project, structure your narrative around the problem, your specific contributions, the design process, the rationale behind your decisions (linking to data/hypotheses), and the quantifiable outcomes.

• Show, Don't Just Tell: Use high-fidelity mockups, prototypes, flow diagrams, and data visualizations to illustrate your points.

• Be Ready for Deep Dives: Anticipate questions about specific design choices, technical constraints, team collaboration, and how you handled feedback or conflicting opinions.

• Highlight Design System Proficiency: Explicitly show examples of how you've used or contributed to tokenized design systems, explaining the benefits and your process.

📝 Enhancement Note: The interview preparation focuses on practical application, strategic thinking, and demonstrating a data-driven approach to design, all critical for a CRO-focused role within an agency setting.

📌 Application Steps

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

• Submit your application through the VML careers portal.

• Curate Your Portfolio: Select and refine 3-5 key projects that best showcase your CRO experience, design process, and proficiency with tokenized design systems. Ensure each project clearly demonstrates your impact on conversion rates or user engagement.

• Tailor Your Resume: Highlight keywords from the job description, such as "Conversion Rate Optimization," "A/B Testing," "Figma," "Tokenized Design Systems," "User Psychology," and "Data-Driven Design." Quantify achievements wherever possible.

• Prepare Your Portfolio Presentation: Practice a clear and concise walkthrough of your selected case studies, focusing on your problem-solving process, design rationale, and measurable results. Be ready to discuss your contributions and learnings.

• Research VML & WPP: Understand their client portfolio, recent work, and company values. Prepare to discuss how your skills and approach align with their culture and their clients' needs in driving digital growth.

⚠️ 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.

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