This book constitutes the thoroughly refereed post-workshop proceedings of the 8th International Workshop on Agents and Data Mining Interaction, ADMI 2012, held in Valencia, Spain, in June 2012. The 16 revised full papers were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on agents for data mining, data mining for agents, and agent mining applications.

Organizational Control for Data Mining with Large Numbers of Agents.- Competitive Benchmarking: Lessons Learned from the Trading Agent Competition.- Supporting Agent-Oriented Software Engineering for Data Mining Enhanced Agent Development.- Role-Based Management and Matchmaking in Data-Mining Multi-Agent Systems.- Incentivizing Cooperation in P2P File Sharing: Indirect Interaction as an Incentive to Seed.- An Agent Collaboration-Based Data Hierarchical Caching Approach for HD Video Surveillance.- System Modeling of a Smart-Home Healthy Lifestyle Assistant.- An Optimization Approach to Believable Behavior in Computer Games.- Discovering Frequent Patterns to Bootstrap Trust.- Subjectivity and Objectivity of Trust.- KNN-Based Clustering for Improving Social Recommender Systems.- A Probabilistic Model Based on Uncertainty for Data Clustering.- Following Human Mobility Using Tweets.- Agents and Distributed Data Mining in Smart Space: Challenges and Perspectives.- Agent-Mining of Grid Log-Files: A Case Study.- A Proficient and Dynamic Bidding Agent for Online Auctions.