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Strategic Account Manager - London
Full-time
London, UK
Posted on Aug 11, 2026
Meet Siena
Siena is the Agent of Record for CX, built for consumer brands like Spanx, FIGS, Brooklinen, and Grüns.
It runs as a connected multi-agent stack on top of a shared intelligence layer: agents that sell, support, listen, handle social and voice across the entire customer journey, turning every conversation into signal you can act on.
The team
We are a small, fully distributed, global team. We have built leverage into how we work, which is what lets a team this size move at the speed we do.
We hire athletes. Everyone here owns real outcomes, defaults to writing over meetings, communicates with directness, and acts the moment they see something worth acting on. Low ego, high standards, fast clock.
If you want to set the bar rather than follow one, keep reading.
The Role
You own the commercial relationship for Siena's highest-value brands: renewals, expansion, executive trust, and knowing your accounts better than anyone. A deployment strategist owns product outcomes for the same accounts, and together you're the Siena pod.
You're accountable for net dollar retention, expansion quota attainment, and executive relationship health across your book. You own our Growth and Strategic segment accounts, not the full customer book, working at the intersection of customer, sales, and your deployment strategist. Expect moderate travel for in-person workshops, account visits, and QBRs.
What You'll Do
Own the commercial relationship end to end for a portfolio of Growth and Strategic accounts, from post-onboarding through long-term growth: build concrete account plans, track impact with data, and hold customers and internal teams accountable when progress stalls
Map every account and build executive trust: maintain a living stakeholder map, build relationships with decision-makers beyond day-to-day contacts, and own the executive cadence so leadership sees Siena's value before renewal conversations start
Drive commercial outcomes: own renewal negotiations, independently identify and close expansion opportunities, and quantify customer ROI in cost savings, efficiency, or revenue impact
Bring product depth to the relationship: understand how Siena's agents work together, explain capabilities confidently, and guide customers on the best strategic use cases
Lead cross-functional execution: turn vague customer problems into clear problem statements and execution plans, partnering with other teams as needed
Who You Are
The Bar: If you're missing any of these, this isn't the role for you.
3+ years in account management with technical, complex software, including at least one independently negotiated $100k+ deal
Startup background: comfortable in fast-paced, ambiguous environments, wearing many hats
E-commerce or CX industry experience: customers respond better to AMs who speak their language
Strong Signal: Not dealbreakers, but what separates a good hire from a great one.
Hands-on AI experience: you've built an agent, automated a workflow, or created a tool, not just used ChatGPT for email
Enterprise experience: managed complex orgs, sold to multiple stakeholders
Close collaboration experience with product and engineering teams
Self-directed: brings solutions, not just problems
Balances empathy with commercial impact, willing to challenge the status quo when it blocks results
Nice to Have: Bonus, not required.
Experience at a native AI technology company
Comfort with API integrations, conversation flow design, and business intelligence tools
Not a Fit If:
You want a fixed playbook and clear SOPs before you start
You'd rather support the commercial conversation than own it
You need close oversight rather than working independently with your deployment strategist as your main partner
Why Siena?
Real ownership. You will own problems, not tasks, with the autonomy to solve them your way and the trust to do it without a manager in your inbox.
Work that ships and matters. What you build reaches real consumer brands fast.
A category we are creating. The Agent of Record is new ground, with unsolved problems and cutting-edge models, not a crowded field to compete in.
A team that respects your judgment. Globally distributed, async-first, low bureaucracy. We hire adults and treat you like one.
Great salary plus equity or stock grants. Own a piece of what you build.
Learning budget. If you are growing, so are we.
AI-fluency by default. Few places will push your work with production AI further or faster.
Our values
The people who thrive here are curious, customer-obsessed, and take ownership without being asked. They fix problems first and explain later. They're direct about feedback - both giving and receiving it - because they care more about getting things right than being polite.
They maintain high standards while moving at startup speed, and they build real relationships with teammates because they know that's how great work gets done. When things get tough, they adapt and keep pushing forward.
Our approach to AI
The people who thrive here treat AI like a natural extension of themselves. They've built their own ecosystem of agents - some for research, others for debugging, writing, analysis, or writing code. They know which AI works best for what problem.
Everyone gets premium accounts (ChatGPT, Claude, Perplexity Pro, Cursor, Lovable) plus a quarterly budget for new tools. But the magic happens in how we share knowledge. Demo days where someone shows off a clever workflows. Slack threads about which model handles a specific use case better. Learning from each other's AI workflows.
At Siena, we're not just looking for people who can do a job. We're looking for people who want to break boundaries, create the future, and reshape industries. If that's you, we look forward to your application.
How we hire
We use AI-assisted screening tools as part of our hiring process. All decisions are made by humans. You can request a human-only review at talent@siena.cx.
Siena provides equal employment opportunities to all employees and applicants for employment without regard to race, color, religion, sex, national origin, age, disability, genetics, sexual orientation, gender identity, or gender expression. We are committed to a diverse and inclusive workforce and welcome people from all backgrounds, experiences, perspectives, and abilities.