Results-driven digital marketing and brand partnerships professional with 6 years of experience at Twitter/X and Socialdatabase. I specialized in luxury and high-end retail campaigns at X, where I developed and optimized data-driven advertising strategies, built strategic brand collaborations, and delivered significant revenue growth for premium clients. With global experience living and working in Japan and currently the Netherlands, I bring a strong multicultural perspective and proven success in cross-functional team collaboration across international markets. Passionate about luxury, fashion, and editorial storytelling, I excel at structuring commercial partnerships, enhancing client satisfaction, and driving measurable business impact. I am immediately available for this freelance opportunity and would welcome the chance to discuss how my luxury brand expertise and partnership-closing track record can help secure and deliver high-profile collaborations for your editorial project.

Kei Yamaguchi

PRO

Results-driven digital marketing and brand partnerships professional with 6 years of experience at Twitter/X and Socialdatabase. I specialized in luxury and high-end retail campaigns at X, where I developed and optimized data-driven advertising strategies, built strategic brand collaborations, and delivered significant revenue growth for premium clients. With global experience living and working in Japan and currently the Netherlands, I bring a strong multicultural perspective and proven success in cross-functional team collaboration across international markets. Passionate about luxury, fashion, and editorial storytelling, I excel at structuring commercial partnerships, enhancing client satisfaction, and driving measurable business impact. I am immediately available for this freelance opportunity and would welcome the chance to discuss how my luxury brand expertise and partnership-closing track record can help secure and deliver high-profile collaborations for your editorial project.

Available to hire

Results-driven digital marketing and brand partnerships professional with 6 years of experience at Twitter/X and Socialdatabase. I specialized in luxury and high-end retail campaigns at X, where I developed and optimized data-driven advertising strategies, built strategic brand collaborations, and delivered significant revenue growth for premium clients.

With global experience living and working in Japan and currently the Netherlands, I bring a strong multicultural perspective and proven success in cross-functional team collaboration across international markets. Passionate about luxury, fashion, and editorial storytelling, I excel at structuring commercial partnerships, enhancing client satisfaction, and driving measurable business impact.

I am immediately available for this freelance opportunity and would welcome the chance to discuss how my luxury brand expertise and partnership-closing track record can help secure and deliver high-profile collaborations for your editorial project.

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Language

English
Fluent
Japanese
Fluent

Work Experience

Business Development Manager at Social Data Base
August 1, 2024 - Present
Boosted revenue by 600% YoY through proactive client acquisition, lead nurturing, and cross-functional collaboration with Account Management and Marketing teams. Spearheaded innovative agency contract negotiations, generating more than €1.1M in new revenue and establishing long-term strategic alliances across multiple regions and diverse business verticals.
Client Account Manager at X Corp. (Twitter, Inc.)
March 1, 2020 - June 1, 2024
Managed renewals and supported clients with data-driven insights to develop and execute strategic marketing plans for business growth. Worked mostly with Luxury brands and Sport Brands, achieving over 30% YoY revenue growth by implementing innovative strategies. Collaborated with agencies to analyze marketing mix models, conducting in-depth valuations of platform presence, driving increased spend and client satisfaction.
Business Development Manager at SOCIALDATABASE, Amsterdam
August 1, 2024 - Present
Led APAC business development, achieving a 600% YoY revenue increase on average through proactive client acquisition, lead nurturing, and cross-functional collaboration with Account Management and Marketing teams. Negotiated agency contracts, generating over €1.1M in new revenue and establishing long-term strategic alliances across multiple regions and verticals.
Client Account Manager at X Corp. (Twitter, Inc.), Tokyo
March 1, 2020 - June 1, 2024
Managed renewals and provided data-driven insights to craft and execute strategic marketing plans for business growth. Worked mainly with Luxury and Sport brands, achieving over 30% YoY revenue growth by implementing innovative strategies. Collaborated with agencies to analyze marketing mix models and evaluate platform presence, driving increased spend and client satisfaction.
Business Development Manager (APAC) at SOCIALDATABASE, Amsterdam
August 1, 2024 - Present
Led APAC business development, driving revenue growth through proactive client acquisition, lead nurturing, and cross-functional collaboration with account management and marketing teams. Negotiated agency contracts, generating over €1.1M in new revenue and forging long-term strategic alliances across multiple regions and verticals. Achieved an average 600% YoY revenue growth through data-driven optimization and client-facing consulting.

Education

Bachelor's Degree at International Christian University, Tokyo
April 1, 2016 - March 31, 2020
Exchange at University at Buffalo, SUNY
August 1, 2018 - May 1, 2019
Bachelor's Degree in Communication and Media at International Christian University, Tokyo
April 1, 2016 - March 1, 2020
Exchange Program at University at Buffalo, SUNY, Buffalo NY
August 1, 2018 - May 1, 2019

Qualifications

Add your qualifications or awards here.

Industry Experience

Retail, Software & Internet, Media & Entertainment, Professional Services, Other