Your choice of collaboration partners may be unconsciously shaped by how vividly they recall shared experiences. This finding challenges the assumption that we select social partners based solely on explicit traits like competence or likability, revealing instead that memory quality serves as a hidden social signal. The research demonstrates that humans possess an unexpected ability to gauge the contextual richness of others' episodic memories during conversation. Participants could distinguish between detailed, experiential recollections and more generic memory reports, even when the factual content remained identical. This detection occurred rapidly and without conscious awareness, suggesting an evolved capacity to assess memory fidelity in real-time social interactions. Most significantly, people systematically preferred partners whose memories contained greater contextual detail when making subsequent collaborative choices. The preference persisted even when controlling for other social factors, indicating that memory richness operates as an independent social currency. This discovery illuminates why storytelling and shared reminiscence feature so prominently across human cultures. The ability to detect and value detailed episodic memory may have evolved because individuals with richer autobiographical recall prove more reliable social partners, better able to learn from past interactions and maintain complex social relationships. However, the research involved laboratory-based memory assessments rather than naturalistic social encounters, and the sample consisted primarily of university students. The findings await replication across diverse populations and real-world contexts. If confirmed, this work suggests that memory enhancement interventions might yield unexpected social benefits, while also raising questions about potential biases against individuals with memory impairments in social and professional settings.