Day One Entrepreneurs & Partners

Day One Entrepreneurs & Partners has pioneered an innovative approach to nurturing early-stage startups with a long-term development perspective. As the leading French seed funding organization, they've established a comprehensive methodology that integrates financial backing with continuous, holistic support. Their distinctive model moves beyond traditional acceleration by focusing on sustainable growth trajectories rather than quick exits, positioning them uniquely in the European startup ecosystem. Founded by accomplished entrepreneurs who bring firsthand experience to their mentorship, the firm leverages practical insights to guide founders through the complexities of business development.

The organization's investment philosophy centers on building enduring companies with solid economic foundations. Their portfolio reflects a commitment to ventures demonstrating potential for sustainable profitability rather than merely rapid scaling. By working closely with founding teams from inception, they foster the development of resilient business models capable of weathering market fluctuations. This approach has yielded a portfolio of startups characterized by strong fundamentals and clear paths to profitability, distinguishing them from acceleration programs primarily focused on fundraising milestones.

What truly sets this accelerator apart is their emphasis on entrepreneur psychology and leadership development. Recognizing that founder mindset often determines venture outcomes, they integrate psychological coaching that cultivates essential entrepreneurial qualities: pragmatism, adaptability, resilience, and data-driven decision-making. This holistic approach addresses both business mechanics and the human elements of company building. Their methodology includes regular workshops, one-on-one coaching sessions, and peer learning opportunities designed to strengthen founders' mental frameworks for navigating the challenges inherent in startup development.

The accelerator maintains exceptionally close relationships with portfolio companies, characterized by high engagement and trust between mentors and founders. Unlike traditional investment models with periodic check-ins, their founding partners remain actively involved throughout the company's journey, creating an atmosphere of shared ownership in outcomes. This high-touch approach enables rapid problem-solving and strategic pivoting when necessary. The resulting trust-based ecosystem has become their signature advantage in the competitive European startup landscape, with entrepreneurs citing this relationship quality as instrumental to their success. Their track record demonstrates that this intensive mentorship model produces more resilient companies with stronger foundations for long-term growth.