Managing Director, Client Partnerships - Mediamath

Job Description

Job Description

About the Company

Infillion is the first fully composable advertising platform, built to cut through the complexity, waste, and opacity that have defined digital media for the last decade. Born from $750 million in investment and the unification of category-defining technologies — including MediaMath, TrueX, Gimbal, Drawbridge, and most recently Catalina — Infillion brings these powerful assets together into a flexible, agentic-ready infrastructure.

We serve media buyers, tech decision-makers, and media sellers through a single platform that adapts to how they work: white-glove managed service, self-service control, or API-based automation. The result is zero-hop efficiency, proprietary AI logic, and a level of data transparency the industry has been asking for. Headquartered in New York City, Infillion powers the world's leading brands, agencies, and platforms. Learn more at

About the Role

We're looking for a Managing Director, Client Partnerships to help grow Infillion's presence across the U.S. market. This is a net new business role: you'll be opening doors with independent and mid-market agencies and brand-direct clients who haven't yet experienced what Infillion's DSP can do, and bringing them in.

You'll be selling something genuinely differentiated. Infillion's open-web DSP is built on MediaMath's programmatic infrastructure and pairs it with value-exchange engagement formats that earn consumer attention rather than interrupt it, Gimbal-powered location intelligence, and Catalina's purchase-based audience data baked directly into the buying workflow. These aren't bolt-ons — they're what makes the Infillion conversation different from every other DSP pitch a buyer hears this year.

This role is national in scope. We care where your relationships are, not where you sit.

What You'll Do

• Prospect, pitch, and close net new business with independent and mid-market agencies and brand-direct advertisers across the U.S.
• Build and manage a pipeline of qualified opportunities from first conversation through signed partnership
• Lead consultative discovery to understand client-specific challenges and connect Infillion's platform to measurable outcomes
• Develop and deliver compelling proposals in collaboration with Sales Planning and Solutions Engineering
• Represent Infillion externally as a programmatic thought leader: at industry events, in trade conversations, and across the advertising community
• Drive DSP adoption by positioning Infillion's capabilities against real client needs
• Partner closely with Client Success at close to ensure smooth handoffs and strong account starts
• Maintain disciplined pipeline hygiene in Salesforce and provide regular, reliable forecast visibility

Who You Are

A relationship-driven hunter. You have a track record of opening and closing net new accounts — not just managing what's handed to you. You know how to build trust quickly and earn a second conversation.

A dual-threaded seller. You're equally comfortable with agency partners and brand-side stakeholders. You understand how buying decisions actually get made, and you work both sides of the table without missing a beat.

A platform thinker. You connect the dots between data, technology, and media outcomes in a way that resonates with sophisticated buyers. You lead with business problems, not feature lists.

A self-starter. Your 30-60-90 is already taking shape. You've identified your targets. You're ready to hit the ground running and make an impact quickly.

What You Bring

• 7–10+ years of programmatic media sales experience, with a demonstrated track record in new business development
• Established relationships across independent and mid-market agencies and brand-direct advertisers
• Deep fluency in the programmatic landscape: DSPs, SSPs, identity solutions, data partnerships, and the open web
• Experience selling multi-layered platforms — you know how to build a value narrative that goes beyond a single product or format
• Consultative and value-based selling skills; you lead with outcomes and back them up with data
• Proficiency in Salesforce and a structured, disciplined approach to pipeline management
• Strong executive presence and presentation skills; you're comfortable in the room with CMOs and senior agency leadership

Benefits & Perks

We work hard at Infillion, and we want our team to feel supported, energized, and valued. Here's what we offer:

• Base salary of $175,000–$200,000 plus commission, with on-target annual earnings of $350,000–$400,000
• 100% company-paid health, dental, and vision coverage for you and your dependents
• Company-paid life insurance, short-term and long-term disability
• Unlimited paid time off — we trust your judgment
• Opportunities for profit sharing, bonuses, and ownership
• 401(k) plan
• Cell phone reimbursement

Infillion is committed to building an inclusive and diverse workplace. We are an equal opportunity employer and do not discriminate based on race, color, ethnicity, ancestry, national origin, religion, sex, gender, gender identity, gender expression, sexual orientation, age, disability, veteran status, genetic information, marital status, or any legally protected status.