One Day Agency, the international integrated agency powerhouse, has announced a strategic leadership transition through an internal promotion and an additional new hire as it positions itself for its 2025 ambitions.
Effective immediately, former senior growth manager Klaudia Szelugowska will step into the role of head of growth, leading the agency’s dynamic growth team with a focus on driving business expansion and profitability. Working closely with founder and CEO Ricardo Seixas, Szelugowska will oversee all client services, acquisition strategies, team management and development, bringing her proven expertise to elevate One Day’s horizontal, agile structure across the UK and international markets – the agency now has offices in Manchester, London, and Warsaw, and a team of 12 passionate professionals.
Joining Szelugowska on the growth team is Shelby Davis, who takes over as senior growth manager. Davis brings a wealth of experience from her tenure as client manager at Notorious Communications (formerly Love Suger Science), a Manchester agency renowned for its creative excellence. Prior to Notorious, Davis held senior roles at leading networked agencies such as Havas Media, PHD Media, and Dentsu Aegis, where she managed high-profile campaigns for global brands in fashion, FMCG, and sports.
Known for her strategic prowess in out-of-home advertising and her ability to forge lasting client relationships, Davis’ hire underscores One Day’s commitment to delivering first-class, results-driven campaigns.
Ricardo Seixas, founder and CEO of One Day Agency, commented: “As we push forward into new markets and deepen our impact in 2025, strong leadership and exceptional talent are at the heart of our strategy. Klaudia’s vision and energy will propel our growth team to new heights, while Shelby’s remarkable track record and passion for OOH bring a fresh dynamic to our offering. Her experience at Notorious and major networked agencies makes her a standout addition—we’re thrilled to welcome her to the One Day family.”
As senior growth manager, Davis will focus on growing brands through cutting-edge, behaviour-first integrated planning. Her appointment follows One Day’s recent successes, including successful international expansion and high profile work with the Aston Martin sports racing brand.
Szelugowska’s transition to head of growth builds on her integral role within the agency, offering her the autonomy to shape the team’s direction while co-leading alongside Seixas. The team is not stopping here, with further hires due to be announced in Q2.
With offices in , One Day Agency continues to redefine integrated advertising for brands of all sizes—from nimble e-commerce startups to elite F1 teams.
