Media Buyer and Operations Specialist

Who We Are We are Assembly – and we’re not like the rest. We’re the modern alternative agency, bringing together industry-leading data, talent, and tech to Find the Change That Fuels Growth for the best brands on the planet, including Lenovo, Lane Crawford, Marina Bay Sands, and more. Our diverse, global community of over 1,600 passionate experts combines global thinking with unmatched local expertise in more than 20 markets worldwide – enabling brands to engage and move consumers anywhere. We use STAGE, Assembly’s proprietary, privacy-centric data solutions platform, to surface powerful insights that transform into actionable brand opportunities. We’re at the cutting edge of new media, technology, and platforms embedded in the lives of today’s consumers, and we’re tapped into how culture and communities’ needs change. We do this while staying steadfast in our commitment to Leave the World Better Than We Found It through measurable social and environmental impact work. Assembly was named The Drum’s APAC Media Agency of the Year in 2021 and more recently named Marketing Interactive’s Digital Agency of the Year 2026. WHO WE’RE LOOKING FOR The Media Buyer & Operations Specialist will sit at the intersection of media buying, campaign operations, client delivery, and financial governance, ensuring media activity is planned, bought, executed, reconciled, and reported with accuracy and consistency. This role is suited to a highly organized and detail-oriented media operations professional with at least 8 years of relevant experience across media buying, campaign operations, billing workflows, supplier management, and cross-market delivery. The successful candidate will bring strong knowledge of offline and digital OOH buying, confidence in managing media owners and publishers, and the operational discipline to keep client workstreams running smoothly. Key Responsibilities Media Buying & Tactical Planning • Translate multi-channel media briefs into tactical media plans and buying schedules across traditional and evolving offline channels, including print, radio, OOH, digital Out-of-Home, and programmatic Out-of-Home. • In-depth knowledge of SG offline landscape. • Evaluate historical pricing, market benchmarks, supplier proposals, and consumer insights to inform negotiations and support future tactical and campaign planning. • Liaise with publishers, media owners, and vendors to secure competitive rates, value-added opportunities, ad format recommendations, and fulfilment commitments. • Partner with client leads and planners to ensure media buying recommendations align with client objectives, performance benchmarks, and budget parameters. Campaign Operations & Delivery Governance • Oversee day-to-day campaign operations across assigned accounts, ensuring timelines, dependencies, deliverables, and approvals are clearly tracked and managed. • Define and implement standardized workflows for media booking, material submission, campaign setup, trafficking, reporting, and post campaign reconciliation. • Coordinate with external creative agencies and internal teams to manage production timelines, technical specifications, material submission deadlines, and issue resolution across formats. • Conduct operational audits and post-campaign reviews to identify process gaps, improve efficiency, and reduce rework across markets and workstreams. Finance Operations, Billing & Reconciliation • Manage end-to-end media billing operations, including supplier invoice checks, purchase order tracking, budget reconciliation, and close coordination with finance teams. • Audit supplier invoices, resolve discrepancies, track under-delivery, and coordinate makegoods or credits where required. • Co-own Work-In-Progress reports, systematically reconciling open jobs, verifying campaign status, and supporting monthly financial closure. • Monitor committed, planned, and actual spend to ensure campaigns remain aligned to approved budgets and client billing requirements. Tools, Systems & Reporting • Maintain accurate and timely data inputs across media management, billing, scheduling, and project management platforms such as Monday.com, STAGE, Coupa, MediaOcean, or comparable systems. • Prepare and present media reports, expenditure updates, campaign status trackers, and post-campaign performance summaries for internal and client stakeholders. • Use Microsoft Excel and other reporting tools to analyze large transactional datasets, reconcile campaign spend, and support operational decision-making. • Serve as the day-to-day operations and execution contact for client marketing teams, media teams, internal client leads, activation specialists, and finance stakeholders. • Build strong relationships with internal teams, publishers and creative partners to ensure smooth delivery and localized compliance. What You Bring • At least 8 years of experience in a media agency, media operations, or buying-focused role, with strong exposure to offline media buying, campaign operations, and financial reconciliation. • Strong tactical knowledge of Singapore and regional media environments, including print, radio, OOH, dOOH, and pOOH campaign setup and execution. • Proven ability to manage campaign workflows, supplier coordination, booking processes, billing checks, WIP reconciliation, and monthly financial close requirements. • High attention to detail and confidence working with numbers, budgets, invoices, media schedules, and large transactional datasets. Advanced working knowledge of Microsoft Excel, including functions such as pivot tables, lookups, and structured reconciliation templates. • Familiarity with media management, billing, scheduling, project management, or data platforms such as Coupa, MediaOcean, Monday.com, STAGE, or comparable systems. • Strong stakeholder management skills, with the ability to coordinate across clients, media owners, finance teams, creative agencies & activation teams. • A proac…